Sticking with MK9 (because all post MK3 characters haven't been introduced in this timeline yet):
1. Sheeva - I really really like the idea of Sheeva. Honest. But so many fans hate her and after MK9 it seems like NRS hates her as well. If you aren't going to do her right, then get rid of her. Stop the suffering.
2. Shang Tsung - Never liked him after the first MK. His role in Kenshi's story is cool, but for the most part I think he's an ass clown. I really hope he's dead for real this time.
3. Shao Kahn - Kahn is fantastic, but I think it's time for him to stay dead. Lets get some other villains a shot. New and old.
4. Liu Kang - I have always hated him. The series needs a new champion... Not some generic Asian character.
5. Kano - I'm just sick of him. I never really found him to be interesting and he was so irrelevant in MK9 that it just seems kind of tired to bring him back again.
6. Nightwolf - Kind of a silly character that went out in bad-ass way. Don't screw it up by bringing him back. He did something awesome (for once), let him have it.
7 & 8. Goro and Kintaro - Before MK9 I would have never listed them. But after playing MK9 and seeing Goro and Kintaro being reduced to mentally challenged four armed muscle heads, I simply don't care about them anymore.
Rain: Lame water throwing persian
Shoa Khan: A bi-sexual 'roided-up gladiator in a bondage outfit. Lame
Is Rain Persian? Or Persian-like?
And Shao Khan is bisexual? How do you figure? If so... I wish to keep him! <3