I think I might do some of Vechs' Super Hostile maps.
They're Complete The Monument style maps, where you can do everything you would normally do in MC (mining, crafting, etc) inside a map custom made to be difficult, and you have to fill this thing called a Victory Monument with one of all 16 colors of wool and the 3 metal blocks.
But you have to find the wool in chests in "fleece-boxes" in each difficult area.
I've watched quite a few Let's Play-ers do them on Youtube and it looks fun >_>