One other thought. I think the butterflies on both of these look too modern and incongruent with the other symbols. I would prefer a more runic, minimalist symbol, but something still fairly clearly identifiable as a butterfly. I couldn’t find anything exactly like what I want via a google image search, but perhaps something somewhere in between the two butterflies on this page might work. I also like the runic aspect of the butterfly symbol on the bottom right of this page although I think it’s too plain compared to the symbols we already have.
A further possibility is to have the butterfly symbols drawn from a side-on view, like a slightly less ornate version of this one, and then have mirror images on both sides.