A few things I noticed
It's like you overstacked on searched but nixed nearly all recovery to pay for it. As stated previously by someone else, I would expect your mirror to be beggar-class poor. You'd get down to like three or four Prizes and run smack into a wall. Premiere Ball is search and recovery rolled into one, and given Call/Collector pulling out the required non-Xs you might desire (the one thing Premiere cannot do for you), I don't think you need Pokemon Communication.
My favorite Mewtwo Counter is Honchkrow. Both Drifblim and Honchkrow counter Mewtwo and Machamp; but unlike Drifblim, Honchkrow can also OHKO just about everything in Lostgar while filling up their bench with useless basics or whatever. This means Weavile isn't even needed, giving an extra slot (assuming one was running Weavile AND an anti-Mewtwo tech).
I don't know if you said this, but if you run a Mewtwo counter, you also need a Palmer to recover it in case your opponent Palmers their Mewtwo, snipes your Basic, etc.