I thought MM good with Raptor vs Mutagenic that can be bad a lot of the time. All in all, I don't think MM deserves a slot, but I'm not sold on the energy package in the deck either. It's just experimenting.
Curious if expressive iteration over manamorphose might work? Gives you sorcery and card selection, and casting off it triggers amulet? For energy producer, what about Gondi machination, if you were willing to go black? Appreciate these are different directions for the deck.
Expressive Iteration is probably not worth the splash. Blue is just so weak in terms of what it adds to the shell. However, EI itself is very powerful, and I could be wrong. Preordain just doesn't do it for me, and I don't like splashing for just one card.