Our group started running the "Redshirts: Adventures in Absurdity" AP because who wouldn't want to be a redshirt? The AP has been hysterical and wrong and highly enjoyable so far.
Our away team consisted of:
Tribble Mystic: (Based on a PF creature "worm who walks" or something like that) we changed our ringtones to the Tribble sound and she sent us 'Telepathic' texts. Declared herself (itself?) the captain of our away team.
Dragonkin Solarian: Telepathically bonded to the tribbles. Because reasons. Alternated between using solar weapon, laser rifle, and sassing enemies.
Contemplative Technomancer: Look at the big brain on him! No seriously, look at his big brain and all of those wonderful skills. Without which we'd probably be lost. Also, marvel at his magic missiles and running away in fear.
Our last player spent one session with the pregen Operative from the AP, and the 2nd session as the pregen Vesk Soldier.
I made an Uplifted Bear Soldier initially, but found out about the Vanguard playtest before our first session. The GM let me switch to Vanguard for amusement value. Starting stats were STR 13, DEX 14, CON 16, INT 12, WIS 8, CHA 10 and I went with the Adiabatic aspect as it was the only one that had Improved Grapple. Given the racial benefits from Uplifted Bear I would have gone with any aspect that granted Improved Trip... if there was one. Instead, I planned to Bear-Hug any enemy that was causing the team problems. For gear I had the required redshirt armor (heavy armor) and brought a pistol and a riot shield. First level feat was Weapon Focus (Advanced Melee Weapon) to ensure I could land hits. The movement penalty from Heavy Armor stacked with the Riot Shield was, thankfully, cancelled by the base speed of the Uplifted Bear. That said, I was regularly outpaced by the couple PCs that still had their full 40' movement speed.
The first session went quite well. My high AC and the GM's wild dice meant I was either laughing off blows, or getting critically hit. Entropic Strike was my MVP as it meant I could target EAC, and my Con modifier meant I was doing a minimum of 4 damage each swing. The BBEG of the scenario did manage to drop both the Technomancer and myself, and almost dropped the Solarian, but I stabilized and was able to get back into the fight before any actual death happened.
The second session (after leveling up) also went quite well. I got a huge amount of use out of Life Science and Perception, and the wide range of skills and the number of skill points was nice. Entropic Strike was still my go-to ability, and the shield usage (including taking actions to orient the shield) was useful as well. Improved Grapple was once again useless to me, despite a couple attempts. The scenario was supposed to end with a space combat dogfight, but it had gotten late and we declared that our ship was fast enough to barrel through them instead. The one combat where I took multiple hits and thus actually had points in my entropic pool, the AC boost would not have made a difference to the roll of the dice. I had forgotten about the Mitigate power, but even if I had used it the one time it wouldn't have made a difference in the outcome.
Due to real life events, we won't get to the 3rd session and play at level 3 for some time, so I can't report further.
If I was trying to build a serious Vanguard for a serious campaign, there would be a few different choices. I'd work with the other Players to figure out what role everyone would build for. My defaults would be Gunner or, oddly, Captain. After all, Diplomacy and Intimidate are already class skills. The only difficulty I see there is the Order action and even then Gunner is still easy. Another change would be a different race, preferably with a higher movement rate and +Dex/+Con for bonuses, with either -Wis or -Cha (probably still -Wis) for the penalty.
Here's my thoughts on the various features of this class:
Presentation: I read this as a tough class that strove to be in the front lines and act as a barrier that absorbed/deflected damage as well as a disruptive force to enemy actions. It trades away damage potential for damage mitigation, but focuses on more combat prowess than utility outside of combat.
Starship Combat: Without even focusing on it, I had a good build for Gunnery between full BAB and a nice Dex modifier. If I had wanted to choose a theme or pick up Skill Synergy to be the Science Officer or Engineer, I could have done so and not felt like I was a gimped character; other classes can do that better than Vanguard, though. Being an average Captain would be easy since Diplomacy and Intimidate would cover most actions, but being the best Captain is a bit more of a stretch since you'd want Computers/Engineering/Pilot for the Orders action.
Skill Points: There is a nice selection of oddball skills, and the 6+Int ranks means I can put ranks in non-class skills if I wanted to for whatever reason. In fact, the only skills I felt were pseudo-required for the class are Acrobatics and Perception. Everything else was gravy and gave me plenty of options to personalize.
HP/SP: This was a very nice thing to have. I would have been in trouble with less HP or SP, but I don't feel like I needed any more.
Armor/Weapon proficiencies: I would have enjoyed having grenades added to the list for two reasons. 1) it would give me something to sink money into since I didn't need a melee weapon. 2) With other motivations to take both high Str/Dex, it would have been nice to toss them at enemy back lines.
Shields: I loved the shields, but stacking the movement penalty _and_ skill check penalty was brutal. A class feature that let me ignore some of the penalties associated with shields would have been nice. Maybe ignore -5' of penalty at levels 2 & 6, and gain +5' base movement at levels 10 & 14? Same with max dex penalty. I know there are upgrades for negating skill check penalties.
Entropic Pool: At 1st and 2nd level, it wasn't worth counting whether I had that pool or not. Did me no good.
Entropic Strike: MVP by a long shot. There was nothing about this ability I didn't like, and nothing that I feel needs changing at low levels.
Vanguard Aspects: Trying to use Improved Combat Maneuvers at low levels was an excercise in frustration. However, I suppose it might be more enjoyable and more useful at higher levels. I really wanted an Aspect that gave Improved Trip to better gel with Uplifted Bear's ferocious charge, but I made do just fine. The skill bonus was useful and I could see the later aspects being useful when they were earned. I don't feel like different Aspects would make as much of a difference in playstyle as Soldier Fighting Styles do, though.
Vanguard Discipline: Plenty of possible options here for further customization. While I happened to take the Improved Initiative one, none of them felt required. I could easily tailor a character to the group they were in.
All in all, if I wanted to play a character who focused on being a meatshield more than a high DPR trooper and did more to lead/protect their team than rack up the highest kill count, I would lean towards a Vanguard over a Soldier.