The outline is white, but the AA on the edges is dark, so it looks a bit odd and blocky. I think having no AA at all would work better than AA than isolated dark pixels - or you could add some lighter colours just for AA, but I don't think that's necessary.
thank you.
yes, I was a little worried about the AA + white outline when I made it, but I left it like this anyways ^^; hmm..
still, thanks for your feedback. : )