Tira mostly. XD She's a blast with that hoola hoop blade. a lot of the time I play as my custom characters. XD I actually managed to make Harley Quinn.
My name is Inigo Montoya, you killed my father, prepare to die. My name is Luke Skywalker, you ARE my father, prepare to die. My name is Oedipus Rex, I killed my father and married my mother. I want to die.
Tira's tricky - it seems like a lot of her moves are self-injuring, and whenever I play her, I think I'm more likely to kill myself than whoever I'm fighting against. I can see Harley Quinn using her style, though.
I usually play as Seong Mi-na or Ivy, who is probably the worst character for a newbie like me to try and learn.
The character customization is a blast - my friends keep playing with it when I'm not looking. So far I think we made Sailor Moon, one of the Evagelion units, House, and a bunch or original characters. I'm going to run out of character slots at this rate.