Hmmm, a SSBB roleplay. It would be cool to try one of those. I definately feel that the plot needs some more work (I was never much of a fan of Tabuu). I don't have any ideas at the moment, but when I do, I'll be sure to suggest them.
As for the application, it needs a bit more fleshing out. Here's a suggestion.
Name:
Nickname:
Age:
Gender:
Origin: (this can be where you put which game they're from, or if they're a creation).
Appearance:
Personality:
Special Attacks: This could be where the B moves are kept.
Final Smash: I don't know if you want to have them in this, but just in case.
History:
Relationships:
Other:
I hope this helps.