Wario always seemed to have decent acceleration and off-road for a heavy character in MK64; maybe he could be subbed for Peach, who in turn, would sub for Koopa, fixing the balance issue. Or something like that. I usually picked Koopa in SMK too, but it was more for the stats than anything.
Incidentally, I'm pretty sure the stats can be messed with by changing these ROM addresses.
Incidentally, I'm pretty sure the stats can be messed with by changing these ROM addresses.