If you like any show directed by Ikuhara and want something similar, you have to watch another show by Ikuhara. This is because his anime isn't similar to anything else besides his own stuff.
Mawaru Penguindrum is a surreal story of two boys doing his best to save the life of their little sister - full of metaphores, great animation and beautiful magical girl-like sequences. It's a story about destiny.
Sarazanmai is a surreal story of three boys who are trying to keep connections with other people. Also full of metaphores, great animation and beautiful magical girl-like sequences. It's a story about connection.
Both shows are equally insane and amazing in their own way. The story-telling is similar, hard to understand at first, then everything connects.