I think Super Strength is mostly fine. The only power people don't seem to like it Rage because of the crash. So while I don't think we NEED a change, here's my little idea for the set anyway:
1. Change Rage to some passive defense power like Tough Hide (having Super Strength would naturally make you a little tougher.)
2. Super Strength users now have a "Strength Level" (a nod to the old Marvel Universe Handbooks.) Just choosing Super Strength makes you Strength Level 1, plus one Strength Level for every power picked from the set, up to Strength Level 10. Each Strength Level gives +2% ToHit and +6% Damage, up a maximum of +20% ToHit and +60% Damage.
If that's not overpowered enough, I'd also make Hurl a Targeted AoE attack. It feels weird throwing a big chunk of debris into a crowd and only hitting one guy.