Um.... I'm starting to doubt you have even played Sinestro now... that or you may just have extremely slow reaction times.
I've even verified in training just now to be sure, but if you fireball on reaction to superman's laser at anything more then close ranges you will interrupt it before it hits you. If you are both trying to shoot at the same time you will defiantly hit first and break his laser. At worst you will trade.
Rock is the hardest move to land properly, but it's best right after they jump, it will hit just before they land (only just clipping them) but in a position where most of the cast can take no action before being hit.
Snare basically you want to use the same way, launch it immediately after they dash (or use a dash move) and it will land a few frames before they can block again.