Random off topic question, targeted at this thread since it is the most recent Magus build conversation I found.
I am researching building a Magus and before I looked at the guides I looked at a couple of different options. When I started looking at the guides I expected to see a magus/eldritch knight build and was surprised when I didn't. It seemed obvious to me but I want to know if there is something I'm missing.
Breakdown of Thought Process:
Magus 15-16/EK 4-5
Pros:
1 extra attack / full attack action
Cons:
Lose the ability to gain 2 wizard spells of every spell tier
Lose the ability to never have to make concentration checks to cast defensively
Lose 1 Magus Arcana
Lose 1 6th lvl spell slot
Caster Level hits 19 instead of 20
Optional:
Trade Counterstrike for a combat feat of choice and +1 to reflex saves
So my thought process is that Action Economy > All, so getting an extra attack per round is worth some of the losses, while significant, from the magus ability.
Again, I'm wondering why I have not seen this build called out as hitting a 16 BAB seems like a high priority to a melee damage archetype, I almost didn't see it as an option not to take EK (arcane archer doesn't really make sense since my magus abilities are melee-centric).
Another build I was looking at is Magus 7/Wizard 3/EK 10
This requires a lot more discussion but again you get a BAB of 16 like above. This build heavily favors a dex based magus and gives you an extra feat in light of that but potentially gets burnt for practiced spellcaster. The reason I chose wizard 3 is because I can still hit lvl 6 spells and after checking this would give access to over 600 wizard spells that the magus does not have access to. This comes at a lot of cost, caster level being a significant one (16 with feat). You lose a lot of magus arcana and your arcane pool is crippled. You do get spell critical which is like the magus arcana with less limitations, but you also have to take broad study so you net out at 2 arcana total. You lose 1 4th, 5th and 6th slot (assuming specialist wizard and bonded item counts as 6th level slot). Given your wizard level is going to be 3 you are limited to like 3 specialist schools that aren't as level dependent, I would say void for +2 all saves, admixture to be able to freely change elemental energy types or controller to get telepathy and shared languages with your charms/dominates.
You could also go arcanist, you would need to get a dm ruling if arcane reservoir and arcane pool can stack (I would rule no but it's worth a shot!). You would lose even more spell slots but gain 2 exploits which could be used to get one of the schools above or a choice of a lot of good bloodlines that aren't too level dependent or a few other decent abilities.
The only sorceror I would consider would be the arcane variant bloodline that lets you use int instead of cha.
The biggest cons for this are the caster level hits, the loss of pretty much all magus arcana and arcane pool and the loss of armor. I would have to really dig into the research but I'm guessing that you could buff yourself up to a similar defensive level with your wizard spells. Which is roughly 75 of each school and like 140 from transmutation.
The benefit vs going pure magus is the spell versatility and action economy. You can get 4 attacks / round + spell, additionally if you crit once in the round you get to cast another spell as a swift action (not limited to a touch spell like the magus arcana). If you run a 15-20 crit range then this is likely to happen almost every round. Also, you can make your melee weapon be your bonded object, in short you're upgrading it at half the normal gold cost.