Smoke: Carryover favorite from UMK3; first character I really put effort into as far as learning combos
Sub-Zero: Has consistently been my main in every MK game since MK1. Any chance i get to slow the pace of the fight down / get a free combo (ex. freeze & clone), I am all for it.
Ermac: My first real main in MK9. At first I just got a kick out of his swag combos. Still my favorite character in MK9. Unfortunately I don't think my play style jives with his keep away style. When I am under pressure, my instinct is to rush down and "hit back" soo....
Sektor: I started playing this character after reading through Tom Brady's living guide. Of all the characters that I liked, Sektor clearly had all the tools needed to get the job done. No matter how deep into the yomi layers my opponent wants to go, I can always go one deeper with this character. Can rush down or zone and has mix ups for days. Although Ermac will always be my favorite and my first choice, I have to say Sektor is the one I intend to main from now on.
Kenshi: Almost forgot, I have to add this guy in. A favorite of mine from the 3d games. Being a huge fan of the Matrix I couldn't help but want to play as the closest thing to Neo. Anyway, I really only play this character when I want to see what it's like to have armor. Every now and then it's nice to decide that, not only will my opponent's attack not hit me, but I will hit them instead.... twice... and have frame advantage.... and build back meter... yea.