My suggestion is simple, add the Paralysis feat into Reverse Swings (thus freeing up 1 feat point that could be redesigned to be something more useful, maybe a Berserker specific charge like Reaver gets). Staggering Blow has very little use outside Reverse Swing, and I think it would make more sense to have "Staggering Blow" as our debuff / buff attack instead of separating them with two abilities (one of which has very little use in PvE outside trash).
Of course, the new feat that would replace it would be linked to Finishing Blow, and it would make sense if that new feat would be a Charge (perhaps a charge that increases the Barbarians movement speed by 25% for 5 seconds?)
Thoughts?