I thought up some others:

Queens of Gaming - Joana Dark (Perfect Dark) vs. Laura Croft (Tomb Raider)
Fighting Champs - Scorpion (Mortal Kombat) vs. Ryu (Street Fighter)
Alien Genocidist - Duke Nukem vs. Marcus Fenix (Gears of War)
Alien of Destruction - Arbiter (Halo) vs. Krypto (Destroy All Humans)
Goatee of Death - Sam Fisher (Splinter Cell) vs. Gorden Freeman (Half-Life)
Nameless Master - Warrior of Light (Final Fantasy I) vs. Doomed Marine
Storm - Lightning (Final Fantasy XIII) vs. Raiden (Metal Gear)

Well originally I was gonna keep it retro but you've got some greato nes here that I'll end up using. And I had just stumbled across the street fight Idea so it was limited to start, but come on it had room for expansion.

You seem limited.
But I can help fix that.

Half-Humans - Alucard (Castlevania) vs. Dante (Devil May Cry)
Massive Swords - Seigfried (Soul Calibur) vs. Cloud Strife (Final Fantasy VII)
Samurai - Auron (Final Fantasy X) vs. Mitsurugi (Soul Calibur)
Iron Stomachs - Yoshi vs. Pac-Man
Treasure Hunters - Locke (Final Fantasy VI) vs Nathan Drake (Uncharted)
Final Fantasy Villains - Sephiroth (Final Fantasy VII) vs. Kefka (Final Fantasy VI)
Strange Weaponry - Soma Cruz (Castlevania) vs. Squall Leonhart (Final Fantasy VIII)
Zombie Killers - Leon (Resident Evil) vs. Frank West (Dead Rising)
Iron Clads - Master Cheif (Halo) vs. Samus (Metroid)
Silent Killers - Solid Snake (Metal Gear) vs. Link (Legend of Zelda)
Whip Masters - Simon Belmont (Castlevania) vs. Ivy (Soul Calibur)
Copy-Cats - Kirby vs. Megaman
Gods of War - Kratos (God of War) vs. Ganondorf (Zelda)
Fantasy Ninja vs. Fantasy Pirate - Shadow (Final Fantasy VI) vs. Baltheir (Final Fantasy XII)

Oh absolutely. That would be really awesome. I'm gonna try and do one a week. So far I've got ryu and axel lined up, Kirby and yoshi, Link vs Marth. Fox versus Falco, and I am pretty sure I had one more. Any ideas you have would be greatly accepted.

I was originally planning to do a "character battle" for RetroUprising.
Can I give you some of my ideas for you to do?