Another thing to consider is ripping and using/referencing the textures from the 3DS version of the game, since those have more accurate colors and shading.
Oddly enough, some of the 3DS models shares UV's with WiiU ones, some don't
For example Mario:
http://imgur.com/a/5fHSPEasily you can tell that the UVs are different, whereas Pac-Man's fire hydrant:
It's the exact same in both versions.
I'm unsure how many textures are the same or not, I don't have them all.
Here's wat my falcon body texture looks like in brawl.
-snip-
Wow, it looks great!