That's a good point on 2. I guess I was assuming that all Steem power is fungible (like all BTC is fungible).

If a publisher built a service on top of Steem that curated to their liking (and essentially mitigated the power of the Steem power of some user), I'm not sure how much success they would have. I think fungibility is pretty important to the success of any service on top of Steem, but could be wrong.