Let me see if I can help out a bit....
Mavado
Do Back+Y then X,X,B X,X,B yields even more damage. Online i dont recommend that combo though. However. Y,X,B X,X,B, X,X,B Back,Forwad+A works 90% of the time for good damage especially if you pull it off after a power up.
Hsu Hao by the wall
X,Y,L L X,Y,Y then kick with A. A yields nice damage and connects by the wall. I notice it always does different damage.
Safe damaging combo I find is simply X,Y,L L X,Y,A
SubZero
Down,Up+Y X,Y X,X,A,L always 38% if all connects 50%
Ashrah
2,2,1,cs, 2,2, cs, 2,2,1,cs - 43%