12, 11 and 4. I prefer somewhat realistic and believable designs, plus they look less quirky and more skillful if that makes any sense.

7- I like the idea that she is still in a dress and like she's hiding her 'pointy thing' behind it
15- attracted to this one because she has LESS clothing (protection/armor/etc) which I think makes her come off as even more confident than the others. Like her stance as well.
17- just like the pointy thing in this one, it's different :)

Well done on your concept drawings, very inspiring... Look forward to seeing which one you chose.

4, 7, and 14 are badass. This kind of roster-esque assembly makes me think of Final Fantasy Tactics' class images for some reason.

Did you reference these clothing designs from anywhere? I love 'em.