We are probably going to play COTCT soon and with the high focus on urban social interaction I thought this might be a good opportunity to try an Enchanter Sorcerer. Party will include a Warpriest, either a vigilante or a witch, and some other third character.
I'd definitely like to be a party face, so something with high charisma is my priority. Might not HAVE to be a sorcerer though.
Am I wrong to think Enchantment will be fun in this campaign? Are there surprisingly large amounts of immune critters? Will I wreck the plot for my new DM and trivialize things too much? Is a human's extra spells known worth the lower DCs compared to the Kitsune? Should I actually be a Mesmerist instead, for the skills? Or should I be focusing on more of your "standard" Caster build with control and utility options?
Anything goes, I'd say. I have an enchantress in my campaign and it works fine (probably because she only joined us in the fifth part of the campaign).
Of course, a specialist wizard is much more of a one-trick pony than a sorcerer, even if he knows more spells. An enchanter, for example, is more or less useless in certain fights (if enemies are immune to mind-affecting effects) and turns other fights into the same 'drudgery' (how many fights with confused enemies can you stand before it becomes boring?). Despite his limited number of known spells, a sorcerer is more versatile and might be more fun to play.
So my advice: both are fine, but personally I'd go with a sorcerer.
As far as race is concerned, Korvosa's population is 90% human, so it is easier for your GM to fit you in when you are a human. The extra skill point and the extra known spells through the favored class for human are also a great boon for sorcerers.
Enchantment should work just fine.
There are critters immune to enchantment-type spells in the AP, but that's generally true of most any type of adventure -- as a spellcaster, you should always figure that at least some foes will be immune to at least some of your spells, and therefore make sure to have a variety of spells that can affect such creatures. Blasters needs to worry about energy-immune or energy-resistant foes, enchanters need to worry about mindless or high-Will foes, transmuters need to worry about high-Fort foes, etc., etc.