I just got an idea while listening Dragon Ball soundtracks. Besides having DBDEV musics playing everywhere in the game, we can only play what we want to listen in the jukebox. Then, I think it should be interesting to be able to play a wanted music in the versus mode.
It should work like this :
- In versus mode, we get another button like the one to change the background, maybe under this one. We could listen to the choosen music right in the characters' selection screen. The button's text should be the name of the music. When we switch the music button, the music switches too. It's like a kind of demo before fighting. And in the fight, we listen to the same music (restarted, of course)

The idea reminds me the Tenkaichi Budokai series.