Finishing up this round of playtesting feedback with the Mechanic. As with the other write-ups I've posted, I'll split my post into sections, spoiler them, and add a TL;DR just so it's all a bit easier to navigate.
I ran my playtests mostly across levels 1-15, as I ran them mostly using the official Starfinder playtest scenarios and field tests. I ran some playtests at higher levels using Pathfinder content, but treated those as secondary to the playtest scenarios.
I ran my Mechanic with a variety of party compositions, mostly with just other Starfinder classes. I eventually started adding Pathfinder classes into the mix, and treated those playtests as secondary.
I tested my Mechanic using different Starfinder ancestries, including ancestries from the Galaxy Guide.
I ran the scenarios RAW for the most part, only adjudicating when something broke or was missing from the rules (or the class's core features). I then started playing with certain parameters, chiefly the Mechanic own features, and treated those findings as secondary.
I generally tested the Mechanic by prioritizing Int, then Dex, then Con, then Wis, but also tested out a zero-Int Mechanic on a few occasions, the results of which I'll detail below.
I tried a variety of guns on the Mechanic.
TL;DR I ran the Mechanic through a series of playtest encounters from low- to fairly high level, using a variety of ancestries and party compositions. After a little over a week, I started experimenting with altering the Mechanic's features to see how that would affect their gameplay. The most unusual aspect here is that I sometimes dumped the Mechanic's Intelligence for certain tests, and I'll explain why further down.
Core Class:
Splitting my feedback on the class's core chassis and feats for readability:
I really liked having a large baseline complement of trained skills and mods. It definitely felt like I was playing a utility character, though unlike full-on skill monkeys my contributions came from a mix of skills and mods.
Although I can sort of understand why the Mechanic was given legendary Perception (so that they can find and disable traps), I don't think it makes much thematic sense on the class. By contrast, I would've quite liked it if their class DC had scaled to legendary, as that would have let them make better use of grenades, area weapons, and other bits of tech.
At first glance, I thought the Mechanic would play similarly to Pathfinder's Inventor, but in practice they play very differently due to Modify. Because modding takes an action and lasts only one round, I often spent a whole turn modding my exocortex and using it, which felt appropriate for the class and felt like my biggest contributions were area control and utility, as opposed to the Inventor's more straightforward Strike damage and unstable actions.
Although I'm personally quite okay with modding being so short-lived, I'm not a huge fan of the generic damage boosts, which I think led to more repetitive and less interesting turn rotations oftentimes. I'd rather have mods be more situational or utility-centric, though still powerful enough to justify spending actions modding.
A strange quirk of the Mechanic is that they have no core class mechanic that uses their key attribute. Some subclasses like the Mine and Turret exocortex do have Intelligence scaling, but the Drone exocortex doesn't outside of certain options, which meant I could bring my Mechanic's Int to zero with the latter subclass and suffer no major consequences besides having only slightly fewer feats to choose from (and I could still pick most available feats just fine). Something as basic as giving the Mechanic a number of starting mods equal to 2 + their Int mod or the like could probably address this.
Before talking about subclasses, a very minor gripe: "exocortex" absolutely did not feel like an appropriate name to describe the Mechanic's subclasses, as none really had anything to do with having complex machinery sitting on top of your body. "Rig" would be a much better name in my opinion.
The Drone exocortex is basically just the Inventor's construct companion, except done much, much better. I enjoyed being able to choose from a variety of different chassis and customizations, and would like that amount of player options to perhaps eventually make it back to Pathfinder's construct companions.
The Mine exocortex felt like trying to reinvent grenades, only clunkier and with far fewer options. I love the idea of being able to control an area with lots of explosives, but found the implementation really janky and needlessly isolated when this could've easily been about generating lots of grenades for free and modifying them in different ways for area control.
The Turret exocortex is interesting in how it lets you shoot from a different location, but I don't think it did all that much beyond that. The biggest issue I had was that, RAW, the turret stopped working entirely below half HP when it got broken, but there wasn't really anything you could easily do to get it working again at low level. Very quickly, I houseruled that you could use Deploy Turret as a two-action activity to heal it to full HP and redeploy it regardless of how much HP it currently had, and that solved that problem.
Though not a huge criticism for what is ultimately a fairly tightly-scoped playtest, I would like to see future subclasses that don't necessarily revolve around area control. A utility subclass that can dish out temporary upgrades to allies could be really cool, as could an actual exocortex subclass focused on cybernetic enhancements.
I'm not normally a fan of a class having lots of core features that might as well be feats, but here I think it works. Being able to mod your tech increasingly easily did make a difference, and made the class even more flexible in a way that felt like a natural part of their core progression.
TL;DR The core class I think is pretty solid. It's not perfect, and I do think the class needs to guarantee that Int will directly contribute to their class features (it's not really the case for the Drone subclass), but overall the Mechanic felt like its own class with a unique niche and interesting choices to make when they weren't just adding their Int to their mine/turret damage.
Feats:
I mostly focused on level 1-14 feats during my playtests, owing to the level range at which I mostly played:
Let's get this out of the way: the Drone's feat progression is completely borked. Even after the recent wave of errata, the feats are at the wrong levels and there's no indicator for what an advanced companion is (is it like an advanced construct companion? If so, why is this a 14th-level feat?). I do not understand why the developers didn't just copy-paste the companion feats from Pathfinder, and that's what I very quickly ended up doing even before the errata.
Broken feat progression aside, I quite liked the range of feat options I had for the Drone exocortex, in particular the special customizations. For the Mine and Turret subclasses, I felt I had a fair bit less choice, and I feel both could have plenty more options if, say, the Mine exocortex let you create temporary grenades and the Turret exocortex let you deploy any gun you had as a turret.
I liked most of the mod feats that were made available, and would definitely like more. There's a lot of room for exploration here, I think.
One feat I think needs a rejig is Critical Explosion. Specifically, it has the same problem as Expanded Splash on Pathfinder's Bomber Alchemist, in that more damage to your core ability (and especially +4 damage at level 1) is such a no-brainer that it effectively becomes a feat tax. Persistent damage on a crit fail is fine, but if the mines need more damage, that ought to be a part of the base package.
Auto-Target I found a really interesting take on ranged Reactive Strikes. It's still quite powerful, but rather than work as a free Strike each round, it specifically controls against movement, which made for actual counterplay. I'd be comfortable setting this as the model for other ranged Reactive Strikes, as I don't think it makes sense to have that reaction trigger at range from shooting when moving or shooting is what everyone's going to be doing practically every round.
I'm a bit confused by Tactical Team-Up, specifically in relation to Coordinated Fire: although there's perhaps a case to be made for triggering a weakness twice, the feat is otherwise straight-up worse than a lower-level feat that does the same thing. I could be wrong, but it feels like one feat was an updated version of the other and the original didn't get removed when the playtest launched.
Because so many of the feats cater to a specific exocortex, I wish there were "baby subclass" feats that let you access a much weaker version of an exocortex, much like the Prototype Companion feat on Pathfinder's Inventor. This would allow a Mechanic to more easily branch out into more feats.
Additionally, and this is also an issue I had with the Technomancer: I wish there were more feats that interacted with ambient tech, whether it's computer systems, tech hazards, enemy gear, and so on. I guess it's difficult to playtest when the bulk of playtesting tends to revolve around encounters, but I hope for more of those kinds of feats in the release version.
TL;DR Although the Drone feat line is completely garbled right now, even post-errata, I found the Mechanic's feats quite fun to choose and use. I'd like to see more mods and more feats that work off of environmental tech in the release version, but otherwise I have no huge criticisms to make here.
The concluding TL;DR is that in contrast to the Technomancer, who I think misses the mark as a tech-focused caster, the Mechanic I feel delivers much better on their class fantasy. Overall, the class's design and balance feel much closer to PF2e in many good ways, and sit much closer to what I expect from 2e classes. There are still some flaws, but most I think are fairly easy to address, and the core mechanic of modding and deploying stuff feels both fun and novel in my opinion. I think the Starfriends did an excellent job with this class overall, and I look forward to seeing what gets added to it on release!
Pathfinder Lost Omens, Rulebook, Starfinder Adventure Path Subscriber
Your feedback seems pretty consistent with what the rest of the community's been saying. I'm preparing to playtest a mechanic this Saturday, and I'm definitely noticing some of those feat taxes you mentioned re: mines. The fun factor seems pretty high based on what I've read, though!
I noticed you didn't include your usual section on ad-hoc class tweaks. Did you not feel the need to do so this time?
It is, yeah! It’s part of the reason I didn’t feel like changing the class all that much: some of the exocortexes could use some improvements, but aside from the Drone progression feats needing a redo, nothing jumped out to me as in dire need of a change. By contrast, the Technomancer had a lot of dysfunction, which is why I was much more motivated to experiment with more changes there.
I'm a little conflicted on mods. I feel like start of turn lets them be more creative since you have limited time to use them, but it makes many of the mods that require extra actions feel really clumsy. Stuff like Desperate Repair, Troubleshoot, or Healbot got used pretty regularly (at least within context), while the various strike modifiers all felt pretty awkward and unrewarding, there were just too many other things to do.
... Biometric Assessor is technically action neutral (since you spend an action to modify and get a free RK), but also felt frustrating because you had to pre-spend the action and then succeed on two checks in a row.
I found myself kind of frustrated with Mechanic feats because they seemed to be divided between like, really obvious choices that directly enhance your build and cute quirky addons that would be fun to take.
I know that's not super uncommon, but building my Mechanic more than any other class it felt like I both didn't have enough feats but also couldn't justify taking some of the feats I wanted at the same time. Thoughts of enjoying the flavor of Multidisciplinary or wanting to take Commercial Customization a few times to give my drone cool gimmicks falling flat in the face of just obviously powerful feats like Coordinated Fire. I found myself wishing I had more feats but also realizing if I had an extra feat I'd just take hunker down or something anyways.
additional lore + skill training or multilingual for a companion don't even feel like they belong in the same category (also a bit of a shame multidisciplinary doesn't lead to anything).
And while I get not wanting to risk monopolizing systems, I have to agree with the OP that it feels odd that the current Mechanic seems to interact with technology outside their own bubble so little... though modify and the modification feats do go a long way to making the class feel techy in a way the Inventor kind of fails to, so still not bad.
Remote Operation exists but it kind of gets thrown in the same bucket as giving my drone speakers. Neat idea but there are so many high functioning feats here ugh. Again I know this is true for a lot of classes but it really felt especially frustrating here idk.