You bring up a good point. Although I never saw smash bros as THE competitive fighter game (that title belongs to SF), it is very competitive nonetheless. Having Namco on board could result in some (better) sexy balanced competitive gameplay.I always wanted costume packs for my Super Smash Bros. characters.
But in all seriousness, they have more experience developing fighters than Nintendo, cut them some slack.
In all honesty the only reason it's "competitive" is because Melee had way too many exploits and glitches to abuse. Tekken, Soul Calibur, etc, are competitive because of their intentional design.
Mind you I don't expect Namco to be making this too far off the beaten path here but they may try to give some advice on balancing. I'm not too sure what Namco's track record on balance in their fighting games is but it has to be leagues better than any semblance of "balance" in SSB.