Wow! I've been looking for this game for a while!
I had played it a few years back, but couldn't remember the name...I'm so glad I found it!
What I like so much about this game is the ability to actually play AS the Pokemon, as opposed to just commanding them in an RPG style...I think that's really epic.
In particular, I love playing as Swellow in this game, since it's extremely fast, and it's fun to just zoom through the screen as Swellow...and Aerial Ace is a pretty decent damage attack that works pretty well on most things in this game (with the exception of Rock types), so that's a win for me.
I also like all the little Pokemon sprites and animations, and your choice of music in this game. It's all hype!
The only thing I'm sad about is how short this game is.