That is a lot of work. >< I'm not going to actually try to replicate too much of the actual game into this. With the fact that there will be other characters that aren't even in the Smash series, those would be hard to put into the system. Definitely I'll put the Final Smash mechanic, but scrap some of the items. Though, since four people fighting at the same time would be chaotic, two people in each match would be easier to handle, and just so the fighting isn't so "unfair," we could use that dice system. The matches would be until someone blacks out, because it's a little too easy to just knock someone out of the stage.
This should be simple, it's tiring to really replicate everything.