Insanely good pixel art, simple but not braindead progression, good use of the pokemon world and characters. This game is great, the only flaw I would say it has is not having a skip button for scenes you've already done, but they go so quick if you just click the mouse real fast so it's not a big deal really, the secret area is annoying to click on even if you know where it is, but the reward for finding it makes it worth the effort.
Between a 4 or 5 star rating I'd say it's much closer to a 5, hopefully the person(s) who made this game works on other ones, and polish up the small negatives to make others that are even better then this one.
And yeah, longer games would definitely be better too.