The first thing that comes to my mind when I think about rented worlds is the current worlds becoming even more barren, and all the fun and drama that will happen when people are allowed to abuse power over each other. Good times.
As for how I feel about rental words, I have already made peoples eyes bleed with my stance on that topic in the past.
In a nutshell, The owner of the world should not have much or any power over other players.
You can find the bulk of my feelings in the following topic and the posts I link in that topic.