This is a nice first build. I dont believe that ninetails is necessary with 4 stadiums and field blower (essentially being able to bump 5 stadiums), and it would hurt your consistency a little. I also think that your M Mewtwo match up is already favorable, so Mew would be useless. IMO, in a...
I think it will see some play with the Tapu Koko and Bursting Balloon. IMO its a really good card, but it seems to be easily countered. Only time will tell, but i'm definitely gonna build a deck with it.