Why is Ginyu a lock? He had 1 fight really, and the only interesting move he had was bodychange. I'd take Recoome over him in a second.
I wouldn't be surprised if the lineup lines up (derp) with Extreme Butouden to a large extent, and Ginyu was in that. I mean, Arc has already put in some work into making the Dragonball Z characters fit into a 2D fighting game, which moves they'll have, and making them feel varied. I assume they also did the thing where they created the animations and then drew over them for Extreme Butouden, so they may have some assets that they can build on instead of redoing everything from scratch.