If you make more, post them here, because I'd love to see them. :3
I don't really have much constructive criticism because they're all wonderful, but I would suggest that you look a bit into the rules of composition.
Haha, this is probably just the art nerd in me being nerdy. Your graphics are wonderful, but I think messing around with the composition a little can make them even better.
It's just a little suggestion, though. Other than that, your graphics are just great.