Umm, well, nice to see you post your works in here but you're supposed to have at least four examples to open up a gallery according Art & Design rules. I'll give you a day so that you can edit your first post and include two more pieces or I'll have to lock this up, I'm afraid. :c
As for what you've posted, I actually think that they look, I don't know, a little out of place? It really doesn't seem like either Raichu or Charizard belong in those environments. Perhaps making a background that actually suited them would've looked better, in my opinion. Drawing Charizard in an area like the charific valley from the anime or something like that, maybe? I do like the colors and the way you did the tree in the first one, though!