@pat

You are giving miners a huge amount of power in your system. Do they have good incentives to make prudent decisions? 

Miners can be made wealthier in two ways:
Increasing the total social surplus created by bitcoin = the good way

Increasing the share of this surplus distributed as mining rewards = the bad way

If miners were representative of all potential beneficiaries from bitcoin it might not be an issue. I don't think they are. There is a significant danger that the system of one mined block one vote will lead to miners assigning themselves excessively large rewards.