assembly ​​​​​​​

Make all features that are available for parts, also available for assemblies. eg Insert Curve.

So this must be a crazy idea, nobody voting. Or is the idea not in the picture anymore?

Amazing, why would I want to reduce the available features to be used on a assembly? An assembly of multiple parts welded, glued or joined, and start machining reference planes? Like is very common when building machines?