Thanks for the criticism :)
Any specifics on how the left-side arm is "a little off?" I don't see anything obvious, but that may be because i was the one that made it haha. Also, head shape: the two are very similar in shape, the only difference is I majorly cut down the size of the plate things on top of his head. Was that what you were refering to? If it wasn't I'm not sure what you meant.
I'll edit this post with the corrections as well as a new sprite I'm working on: Bellsprout.
...Take it higher, take it higher, 'til the roof is on fire. Take it higher, take it higher, let's burn it up...