SF1: Depends on which player side I was on, but it was normally Ryu
SF2WW: Dhalsim, because I got 10 wins first time I played just spamming cr.FP
SF2CE: Dhalsim, finally learned a few strats like anti air slide, fireballs, and how to mash noggies
SF2T: Guile and Sim. Picked up Guile when some asian kid whopped my ass with him 10 games straight. He was from Cali visiting, and he used Guile in a manner I had never seen. I know I had to use this character
SSF2: Really no main. I played mainly the Genesis version, and I experimented with many other characters.
SSF2T: Had a few, Ryu because he had the easiest super to pull off. But eventually I went back to Sim and Guile
SFA: Charlie, was finally able to do j.hk, cr.lk, st.lk, fk. Eventually learned his somersault super as well. Also mained Guy and Sodom for awhile since I was a FFF (Final Fight Freak)
SFA2: Charlie, Dhalsim, Guy.
SFA3: Mainly stuck with Charlie and Sim, but experimented with most of the cast. Dropped Guy because of how difficult his execution was in the game.
SF3:NG: Oro and Ryu. Oro reminded me most of Sim, and Ryu was pretty familiar. I didn't know parries were in the game until years later
SF3:2I: Only played it a handful of times, but I only really played Hugo
SF3:3s: Started out with Ryu, but didn’t like him. Played Urien,Hugo, and Q for most of the time I played the game. Then I sold out and started playing Chun-Li because I was tired of the bullshit in the game.
SF4: Originally intended to use Sim, even posted on the Sim forums before the game came out. But Sim felt limited and weird. Guile felt a little more like his ST self, and I rolled with him despite his low tier status.
SSF4: Still stick mainly with Guile in competitive play.