If you have access to cursed earth yet in your world you can get a great farm going. If you set it up in the end it will only spawn endermen, i use fans to push them and use diamond spikes to kill them and you can enchant them with looting if wanted. This setup doesnt take energy and very easy to set up, the most expensive thing was diamond spikes which i believe iron spikes can be used but i used diamond spikes and reaper ench. to get souls for draconic evolution and an XP farm.Yeah I'm doing that atm. I'm thinking I *might* be able to get a stable loonium setup running earlier than a decent enderman farm in a given new game. Maybe.