Liu Kang, because my heart lies with boyscout heroes type of characters. Always. And if I play a game with choices, I will always do good. Would it be Mass Effect or inFamous, my character will become an ideal to strive towards.
To me Liu Kang is Superman of Mortal Kombat saga. He is a shaolin super hero and Earthrealm's champion of Mortal Kombat tournament. He saved world 4 times in a row (in MK4 he saved the entire universe from Shinnok's domination). He is very good and kind person, who cares about his friends and he knows what forgiveness is, when he shows understanding towards Shujinko and him been used by Onaga for evil, but Shujinko thought that he was serving for the greater good.
Mortal Kombat Deception showed that even death can't stop Liu Kang from helping people, his friends and his soon-to-be-wife especially:
He didn't even minded to work with Ermac, his former enemy, because Liu Kang saw that Ermac is trying to be a force for good. Liu Kang believed in him and asked for help to rescue precious for Liu Kang people.
I also like how Liu Kang is a representative of Bruce Lee in Mortal Kombat series and eventually he grew into his own character rather than just a copy of an actor. The way he moves in Mortal Kombat X is outstanding though, I love all of Bruce Lee mimicking he is performing in game, because it suits Liu Kang.
This is how I pick up a character. I find the one I have spiritual connection with in the meaning of his story, personality and allignement to good, how he moves and looks is also important, because I like to play a badass looking hero.
Only then I start learning the gameplay of the character and no matter how hard or low tire his gameplay is, I will stick with him forever.
I will forever curse NRS for what they are doing with Liu Kang's character since MK9 (and will forever hate them for what they did with Superman in Injustice). I want my boyscout shaolin hero from original timeline back. His intros in MKX sucks most of the times, because he became too cocky and arrogant and it doesn't suit him at all, looks like a bad mixture of Johnny Cage's blood was used on Liu Kang.
Still, my hope for the Hero of Mortal Kombat to come back once again and remain like that forever.