The controls are simple and it kills some time but if you intend to make a sequel you could label each different power up differently and maybe add in some gun upgrades and tougher enemies, but this is still good for a first game :D
I have to say though with a game where battling takes a big part you would need to do alot to that area. Such as having ALOT of different move animations and animations for the health bars when they take damage, also the text was a bit fast. :P And what were you planning in the way of pokemon? 150 odd new self created ones or already existing pokemon? if you were to make your own it would take longer to make but the game would have a sense of originality to it. In the way of story I'd like to see something not done before, usually in pokemon games you get badges and go to a big showdown of elite trainers, but no pokemon game to date has had a plot where you hunt down a pokemon for revenge which would be an EPIC story (such as pokemon killed loved one you, want kill it...). In terms of XP and leveling you could have a points system where you choose what points go into ATK, DEF and the like rather than the game choosing for you and when you evolve you can have more points every level. all in all things like this have potential so all you have to do is put in the effort :D
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