Honestly, I wish the game had more actual gameplay.
But honestly, you can only do so much when your #1 objective is to put as many characters are you can into the game.
I liked Daimao better in Super DBZ, but he's pretty cool in Sparking! Meteor too.
My favorites were Akkuman (his What-If against Freeza was BAD ASS), Hatchan, Arale, Granpda Gohan, and of course, Roshi. I think I used Akkuman the most though.
And GOD, Ginyu's body change is fucking horrible in this game. I dunno if it was like that in Neo, but I was horribly disappointed.
edit: Oh yeah, I just remembered that the Akkumaito Kousen (Akkuman's ultimate) is a pretty decent balancer, since a lot of the super powerful hard-to-beat guys are evil.