I think it would be cool to build massive cities with a certain theme. I think that everything in this world should have creative because then people could build really sweet looking things without having to worry about having all the materials. Also it would be nice if we could maybe have a competition section in the world where people compete to see who could build the better looking building. Maybe have a certain theme for the competition or a time limit. The last just course that we had was really good, I'd like to see more of things like that.
The addition of taxes I think is a bad idea because the money for the taxes are not going to anything in the world (at this point) and why would someone want to pay to build where there are other worlds with tons of other places to build for free?
And yes a sky full of boobies would make this world the best one ever.