Ditch the Cosmo for another Night Mantenaince, go with Prof. Oak's Visit over Holon Adventurer, and remove Speed Stadium for a Team Galactic's Wager.
Also, how many Dialga Lv. X and Holon Castforms do you play, you gave no numbers.
Ok, the reason for playing this game is to have fun, not to win all the time. It starts to get boring after awhile, using the same deck. You need to switch it up at least once in a while, and others stop having fun when they keep facing the same decks 1000 times. I mean, at this point, you...
Well, my favorites have to be Street Fighter 2 ( I would spend, like 10 bucks a day on that game for months, which explains my current financial situation:biggrin:), Time Crisis ( all of them), any Mortal Kombat game, and probably House of the Dead.
The main problem with just two decks is the lack of creativity. The only thing your creative in is how your "beast" deck gets setup. It's good for players who are just starting, and can't get the creative juices flowing, but now, its just getting ridiculous.
It has the potential to T2 some decks, but other than that, late game, I think it would constantly lose. If it wins more than 4 states, I would be surprised.