I got a long list:
Street Fighter Alpha 3: Akuma, Sakura, Dan
Street Fighter 3 Third Strike: Akuma, Ken (I've also taken a liking to Ryu and Chun lately)
Ultra Street Fighter 4: Akuma, Sakura, Dan
Street Fighter EX Plus Alpha: Akuma, Sakura, Garuda (and a bit of Skullomania if I'm bored)
Street Fighter EX2 Plus: Garuda, Kairi, Skullomania (and a bit of Shadowgeist)
Akuma is my main in SF, if you couldn't tell lol.
Mortal Kombat 1: Sub-Zero, Scorpion
Mortal Kombat 2: Sub-Zero, Jax (and a bit of Scorpion)
MK3: Sub, Smoke, Cyrax, Sektor (and Kano, somewhat)
UMK3: both Subs, both Smokes (H. Smoke is actually the character I use the most here), Cyrax, Sektor, Scorpion, Reptile.
MKT 32 bit: same as above, but add Noob Saibot to the mix.
MKT 64 bit: same as above, but there's only 1 Sub here.
MK4: Sub-Zero, Scorpion (I actually think I prefer Scorpion here), Reptile, Noob Saibot.
MKG: same as above, but add in Sektor (he's cheap as shit though)
MKDA: Sub-Zero, Scorpion, Reptile, Cyrax
MKD: Sub-Zero, Noob-Smoke, Scorpion, Ermac
MKU: Same as above. I occassionally play as Shao Kahn and Goro but I wouldn't consider them mains.
MKA: Sub-Zero, Chameleon, Noob, Smoke, Reptile, Scorpion. I don't recall playing with Cyrax or Sektor much here.
MKVSDCU: Sub-Zero, Scorpion, Batman
MK9: both Subs, Smoke, Scorpion, Reptile, Sektor, Kratos, Jax. (I used to main Noob, but ultimately disliked his playstyle here. Also mained Cyrax at one point, but I still like him but not enough to be a main)
MKSM (for shits and giggles): Liu Kang, Sub-Zero (and in VS), Reptile.
Tekken 1: Kazuya, Heihachi, Law, Paul, Lee
Tekken 2: Same as above, but add in Devil and Lei.
Tekken 3: Heihachi, Jin, Hwoarang, Lei, Law, Paul.
Tekken Tag Tournament 1: Same as above, but add in Kazuya and Devil.
Tekken 5: Heihachi, Kazuya, Devil Jin, Paul, Law, Lei. (I don't recall ever playing much with Jin, or Hwoarang in T5)
Zero Divide 1: Zulu, Cygnus, Xtal, Neco, Zero.
Zero Divide 2: Cygnus, Zero, Neco
Zero Divide 3: Same as 1st one barring Xtal.