The final Dragon Ball will probably be with bandit Yamcha. He was a pretty important ally during Goku's younger days and he was with Goku during most important events, like when Goku transformed into a giant ape when they were captured by Pilaf, plus he was supposed to be Bulma's leading man.
I hope we get minor characters like Oolong, Puar, Uranai Baba, the Referee guy, and Dende.
Anyway that Dragon Ball Z Carrot (seems like this forum censors the first two syllables of Goku's true name) game looks fun! There's actually good environmental destruction this time around. There seems to be combos or moves that can send enemies flying straight into mountains. If you pound them from above, they crash to the ground and form a crater. Punching or kicking someone away also causes the ground to get wrecked. I'm so glad they finally paid more attention to the environmental destruction aspect. When I was a kid, this was what really made me interested in Dragon Ball. Never have I seen back then a show where mountains and entire cities could be blown up by energy beams or characters getting smacked thru them.
Outside of actual fights, Goku can do sidequests not related to the Dragon Ball story. He can even do hilarious activities like fishing (by attaching a tail to his butt and wiggling it in the water!). Goku can even hunt for food... as in he smacks deers around and he gets meat lol!