Sets are designed to be played with, and balanced around SOs. This to be taken into account whenever balancing a set or reworking a set to bring it to a point where it can function.
SS as it works right now, sort of functions, due to the lower-DPA/DPS nature of its attacks, and essentially only functions decently / well due to Rage.
So, either the powers need to be adjusted appropriately in terms of base damage, the attacks given an AoE like Rad Melee is with successive hits to help with it's lack of AoE outside of Foot Stomp.
Rage should I think, function kind of like how the Adaptations do for Bio Armor, except being on-use ability, rather than a toggle, activating it gives a flat -10% all res except Psi, -10% all def since you're recklessly going into battle, or focused on only hitting the enemy as HARD as possible.
Giving it some -recover or flat endurance increases for SS attacks, which can be mitigated by either picking a set where it gives you additional recovery, or grants endurance based on say, Consume, Power Sink, or simply SOing more endurance reduction in the attacks, or additional recovery enhancements into Stamina, and furthermore enables the small PbAoE's for it's Single Target attacks / +damage boost, with the damage crash applying whenever the buff falls off, and can no longer be stacked, retaining the enormous boost in damage / ToHit, with the base increases to the individual powers to begin with to compensate for the loss of stacking.
I think this would be a middle ground between most of the suggestions put forth so far.