I'm currently playing a peacock-heartbeast Bjornaer in a PbP game...
https://forum.atlas-games.com/t/magi-characters/11830/1 has our characters, "Pavo" (latin for peacock) is mine. I took stats from a partridge in LoM and made it more imposing, and then the SG adjusted slightly.
For magical powers, I would follow this