I mentioned this idea before,but I think it would be interesting to detach D3 from all worlds. This would leave D3-only 'floating' worlds for beginners; they would be fewer in number, but also contain a higher percentage of human coaches. When a coach decides to leave D3 he can then take his resume to any other world and apply for D2,
One downside is for the D3 'lifers' that want to stay at their favorite D3 school, but with the recent dumbing-down at D3 you might see fewer of those guys. And clearly they now treat D3 differently anyway.