My favorite character is Zer0 because he clears the playing field quickly and in a fashionable manner, being an expert on head shots and critical damage. Playing subtlety and delivering serious shock damage in a crew of gullible enemies.
My favorite gun is the bowie maggie due to it's damage output and mixture of my 2 favorite gun types, Pistol and Shotgun. So that means it's a ... Potgun! But aside from that, it's a pretty magnificent shotty-peashoot. and not only that, it's a Jakobs! So more damage all the way!
edit: I don't own any of the DLC's but I'd <3 <3 <3 it if I could get a mechro-mancer DLC... But since I don't own anything, I will have to play with luck!