I'm afraid it's can't work like that. It's looks kinda "black hole": new BTCs could be sold only at price that cover up bills (hardware+electricity) for proditable mining, as long as demand exists (Bitcoin have benefits vs other payment systerms), price'll grow. How much % of miners doing non-profitable mining, just for ideals? I'm sure it's a low % of hashpower (and maybe a low % of people as well).

So there'll be no reasonable equilibrium in foreseeble future, we've miners wanna do profitable business and arms race. Take creation of ASICs as proof. Idealists'd be still mining at CPUs.

Personally I see no bright future for PoW and looking into other PoX. Maybe PoS'll win, maybe other Proof-of'll do.