Back in the day I also wanted to visit this but the formula was to include distance as I thought that the longer links should only do traffic when necessary. You can see OSPF Costing if you want to check the opinions at the time.
I like the complex method and the formula that you’re using. The bridged UBNT devices will pose a challenge but an admin can manually calculate those when they’re setting up the links.
It will have to based on reporting/automated emails and then manual applying of the changes. If it was automated the entire network would go down and who knows how the RBs will cope with the sudden rebuild of the routing table.