Yup predator and shinok definitely getting the nerf hammer,
Currently over at Test Your Might, sub zero (cryomancer I believe), erron black (gun slinger), takeda are getting buffed
I think in Sigma 1 it was mostly level design changes and AI but Cyber probably knows more.
Have you played NG2? Its like a whole new game compared to Sigma 2. I do love Sigma 2's co-op though but whenever I want to do story mode its a no brainer to do it on the vanilla version. So much more...