Kung Lao: I know he's great in MK9, a big part of the story, and I'm cool with the personality. I just can't get past the hat. Not wearing it, but using it as a weapon. It's subjective and maybe irrational, but even if he was S+++ tier, I can't do the hat-weapon. I get it, he's cool, and I love the Ip Man thing, but I'm just not digging the Oddjob hat.
Jason: It is hard to be interested in someone with literally no personality. He doesn't talk. He doesn't do much but butcher campers. Freddy at least had personality. D'Vorah might be an insect and Reptile is a, well you know, but they at least talk and do stuff. Jason doesn't do much but butcher and maybe photosynthesize. I can't relate. What are the f--ing intro dialogues going to be like? "You have trespassed into the Emperor's Realm, prepare to die!" "Tch tch tch... ka ka ka...." No offence to Jason fans, just not for me.
Raiden: Just not a big fan, though I wanted to be. "God of Lightning" has so much promise, but he just seems to be lame so much of the time. Lame in the game, lame in the movie, lame in the comic. Maybe Story Mode will change my mind, but for now: no interest. Sorry Raiden fans, but just not for me.
Honorable Mention: Shinnok's Necromancer variation. Wow, those little dainty skeleton hands do not look cool to me. Shinnok looks a lot better than earlier incarnations, Count Chocula hat notwithstanding, except the skeleton hands. Maybe if they made them bigger, like Skeletor had big hands, idk.
I want to add that I am thrilled with what I have seen of MKX overall and don't want to come off like I am not excited or a h8er. I think there have been a lot of improvements overall and there's plenty of revamped characters that have piqued my interest. This thread did ask what we aren't liking, so there it is.