My company’s UI Component library has a few components that only serve as layout mechanisms for other content. We have things like vertical stacks and horizontal rows. They have a few options in them that are basically equivalents to the AutoLayout features available on Frames. We do this because we have several development teams (and not enough designers) and trying to ensure they all understood the pattern library nuances was unmanageable.
For consistency with designers and developers, it would be very handy for me to be able to build these layout components and use properties to control the behaviors, instead of requiring the designers to remember all of the specific API options and replicate them manually within each design. However, because we can’t add layers to component instances we have no way to accomplish this.
If there was a way to designate an area within these components as editable in an instance we would be able to accomplish this, which would really cut down on the education and discussion required within our department.