Well, Mastercoin won't work if Willet will have 51% of all coins long term.
The economical stability of the system requires that the coins become more distributed anyway ... so I believe that a sort of PoS system is indeed the correct solution (the system doesn't necessarily need to award new coins to voters, although it's a cool incentive to encourage everyone to vote ... even without new coin generation, just a voting structure based on ownership is good enough).
You can do that but that is not democracy. Mastercoin would be a corporation at best and inherent all of the mistakes, flaws, and issues that many people have with the current ways of doing things. I think Proof of Stake does not work very well if it's supposed to be a democracy or for community decision making. It does work fine if the goal is to maximize profit because if the goal is only to make Mastercoin as valuable as possible and nothing else what you have then is a Mastercoin syndicate and not a foundation. That syndicate should be taxed.
One-vote-per-user just isn't going to work. Mastercoin, just like Bitcoin, cannot be tied to regulation, centralization, and thus identity-verification.
Then Mastercoin is a corporation, the voting group is a syndicate, and it should be taxed.
You can't adopt tax free status without having an actual democracy. An actual democracy means 1 vote per head.
Not going to happen. Mastercoin is and will remain decentralized, and will become more decentralized as Willet's coin ownership dilutes (he himself stated him losing 50% as one of the milestones of the project).
Dacoinminster has too many Mastercoins to convince anyone that it is decentralized. It's more decentralized than Ripple but cannot compete with Colored Coin. Mastercoin is as much a corporation as Ripple and the foundation cannot remain tax free unless it acts like a foundation and not a corporation. A foundation has members and members are all equals.
What sort of gaming to you fear if it's anonymous?
It will be controled by its users in proportion to how they have a stake in the coin.
Otherwise you could hire a million Chinese people that don't have anything to do with Mastercoin to spam the voting process, just like the gold-farmers of today. It's just not a good system.
Any anonymous system can be corrupted by coercion. Any anonymous system of voting doesn't allow anyone to know who voted or if the votes are even legitimate. If you want to just let whoever has the coins at that time to vote on the direction of Mastercoin then go ahead, but don't make it part of the Mastercoin foundation and don't be surprised if a bunch of corporations end up owning Mastercoin as a protocol because they buy all the Mastercoins and tame it.
Verification is important if you want an actual democracy. If you're trying to be fair with your votes then each member should get a vote. If you're not trying to be fair then just let dacoinminster have complete control and not bother with voting. Voting gives only the illusion that he is relinquishing control when his votes are worth more than the average vote.