Chris, I personally would not want my variant being randomly changed by alterations in Main.
I too would prefer the variant not to be linked until I chose.

SFW and Stky are probably identified in Main by an ID, which will not therefore register in the variant.
Xara has awkward issues to address with Names across variants still.

When Xara went forward with SmartShapes, the traditional and solid Snap to Objects went West.
Same for Web Blocks. You have to knife and fork inside to achieve the simplest of tasks.

RoAP necessarily cannot work as the WBs are Shared and RoAP & Share do not mix.
Be interested to see what a Live Shared object could do.

Acorn