so while browsing on reddit I stumbled across a couple of things that help Windblade's stability:

https://www.reddit.com/r/transformer...indblade_more/
(change the rotation of the existing heels)

shapeways custome heel part:
http://www.shapeways.com/product/L3Q...ionId=58936068

tfw2005 thread about above custom with some photos and discussion:
http://www.tfw2005.com/boards/radico...apeways-2.html