If you want to peg coins to something, you need to get real-world info into the chain to adjust supply. There are two ways to do this: trust someone, or do it by vote and trust voters to do what you want.
In other words, your proposal is effectively the same as "let coin generation parameters be setr by vote" and "hope people will vote to peg prices".
I described a scheme for doing this here:
http://forum.bitcoin.org/index.php?topic=24929I plan to build such a system after meeting work deadlines, about 4 weeks.
I looked over your proposal. It looks very interesting. Allowing people to vote on how many coins are generated is very different than having them vote on what they think the USD/bitcoin exchange rate is. If I'm understanding your proposal correctly, early adopters would vote for less coins generated, and would use their CPU/GPU power simply to prevent other people from getting coins. Newcomers would vote for lots of coins to be generated. That doesn't sound like a recipe for price stability to me, but maybe I am missing something.