1) It's OK for different users to see different views of the site. Reddit moved to predefined subcommunities, but this could also be done dynamically. A single 'top page' won't cut it unless users have the ability to block and filter.
2) It's OK to partition the site. While one wants consistency, it's OK to pretend that some posts were never made. You can't have things disappearing from the middle of reply-chains, but there's really no difference between a post that's never made and a post that's not shown to everyone.
3) Not everything functions best as a one-person one-vote democracy. I'm all for the benevolent dictatorship PG and those whom he delegates his power to. While transparency is often preferable, sites like this tend to fail due to lack of use of power rather than from unchecked use.