Please help me improve these 3 decks.

Ok with the machine deck you need to put in a lot more monsters or you won't get anything near the full power of the chimaretech overdragon. Also there's no point in having the cyber twin dragon and cyber end dragon unless you actually have a cyber dragon or three. Get the x-head cannon and the vwxyz fusions. they're very useful because they don't need polymerization. I think you are focusing too much on trying to get cool cards. Maybe add reflect bounder and jinzo. You have way too many spell cards your going to end up with just spell cards in your hand a lot. As for the other decks... the crystal beast deck has potential but isn't really good enough. I'd say the best deck is the mill deck. Good luck!