Came across this, thought I would mention it here for consideration.
“The OpenGEX format was created because Collada, the open standard that we all hoped would provide a well-supported asset exchange format, has proven to be an unreliable mess. The most common source of problems has been the poor quality of the Collada export plugins available for software such as 3D Studio Max and Maya, and we attribute this to Collada?s over-engineered design and its mutating under-specified format.”
Comparison with collada:
opengex.org/comparison.html
Has plugins for blender, maya, 3ds…
opengex.org/