Wii was never a good console for fighting games, so I doubt it.
You want good fighting games, get a PS3. ^^
Or get an Xbox since they both have the same fighting games and some fighting games play better on Xbox than PS3 (like SF4) but some games run better on PS3 than Xbox (Like Tekken 6).
By "running better" I mean rate rate. Not that Tekken on the Xbox is bad, but it's not consistent and dips
very slightly.
However I think you actually want an answer though so(!):
Tatsunoku vs Capcom
Guilty Gear XX Accent Core Plus (This is better on Xbox/PS3 and was just released 2 weeks ago in HD with online)
King of Fighters collection
DBZ: Budoukai Tenkaichi 3
and lets not forget Super Smash Bros Brawl. While not supposed to played competitively,it's still damn good!
Get yourself a Tatsunoku vs Capcom stick, mod it with Sanwa/Semitsu parts and have fun.