I actually do not assume that Peter was reset. But I might be wrong.
What I would *really* like to see is a division between "Natural" and "Synthetic" abilities.
So Peter was an Empath naturally (hero parents) and could vaccuum up powers, using them at any time. But then his father permanently drained his abilities and he resorted to the formula to save his brother.
His new, synthetic ability is weaker -- so he can only use the powers of those around him, not access the full suite (except when Ando super-charges him, perhaps...) That *still* allows him to face Sylar, since he would automatically have all the same tools at his disposal in a showdown. It also means that no matter how much they power Sylar up or down, Peter could STILL always match him toe-to-toe.
They could do the same thing to Hiro -- give him back his power, but no Time Travel without help from Ando. Then he could just teleport and slow time to a crawl... which is still ridiculously useful.
I doubt it will happen, but that's what I would LIKE to see. And since I got part of my wish about Hiro, maybe I'll luck out. I still think it would have been great to see him show up in the future, when Ando is discovering his new "Super-Charge" ability, as bad-ass Hiro 16 years older (and with the formula in hand).
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One last thought: Someone up-thread mentioned that Peter couldn't get invisibility back if his powers were reset. Umm... Why not? Nothing has happened to Claude other than he went (deeper) into hiding.
They proved last season you could find him with Infrared goggles and he only bent visible light... Peter could theoretically find him again if he needed to do so.