Berserker looks a bit like Sonya, so I'll probably give him a shot. I'll try Tarkartan since I liked playing as Baraka in MK9. Acidic looks like it'll be really powerful in certain matchups as well. Sektor is probably my favourite out of the group so far. Smoke looks fun too.
Bo Rai Cho and the other variations don't seem really interesting to me, but I'll give them all a fair shot. Of course I also said I was going to learn Tremor...