The game is pretty damn fun, but I wish they branched out with the DLC chars.
Round 1 was Lobo (ok cool), Batgirl (another Batchar!), Scorpion (Well, what?) and Zod (ANOTHER SUPERMAN)
Round 2 I've heard will be Martian Manhunter (sweet!), Red Hood (More...Batchar...), SubZero (I OWN MK9 STOP IT), and Power Girl (MORE SUPERMEN)
I'm not a huge DC fan to begin with, but I wish they would have added more variety like Zatanna or Black Canary or Darkseid (I'm assuming DS will be in a sequel if they do one thou)