Nico Nico Nii!~
If there's too many, there's too many. A lack of focus on specific Pokemon makes a deck have issues running smoothly and quickly, no matter what their abilities and attacks are. Those 2-1-2 lines you have greatly reduce consistency when there are so many of them.
Renpuu's suggestions should work pretty well, and you should be able to easily pick up a promo Mewtwo EX for $5 to $10 off of eBay before States (just make sure you're not buying the Jumbo card or the older ex Mewtwo from Ruby & Sapphire).