If you're cool enough, you can import any model and it doesn't need to match the original character's size.

Yep, as far as I know, since in Brawl animations override translations, it doesn't matter where the bones are in the t-posed model because Brawl will do whatever the hell it wants with them anyway, so, in theory, you shouldn't have to resize the character when rigging them to someone else's skeleton, just position the bones to fit, and it still shouldn't desync or anything.
IN THEORY!
I will also warn you beforehand, I and mostly everyone else will only be downloading Roo's version of Flandre due to clear evidence of moveset and animation planning.

I know I will be downloading Roo's. He seems to have a better idea of what he's doing.
Well there isn't any random lag in the game anymore.
It's not ready for release just yet though, I'm trying to do some other stuff that isn't working right now...
Well, that's pretty freaking awesome.