Yes please!

Yes please!!  Including this would allow users and DB Admin to work together on lists. Undoing the delicate balance created to manage multiple contacts is a serious disruption to the process; it drives DB staff back to the trenches for--what could be-- simple lists.

We currently manage who receives what (within big organisations) from our office based on the relationship attribute. This is because some contacts will receive everything (a primary contact) but then we might have one primary contact who receives only event invites, and then a different contact for receipts and invoices, and a different one again for marketing comms as well as event invites. 
We are hoping relationships will have custom fields functionality. Until then we can't move our DMs completely over to NXT.