Under the current system, there are multiple problems with gear being unique. It's needlessly inconvenient to get a second ring. If they want to keep the Unique system, all they need to do is make rings Unique(2), meaning that you cannot have more than 2 of a single ring. Problem solved.

But honestly, Unique is also painful from a glamour perspective. If I have 4 max-level casters, they can't easily share the same gear without also sharing the same glams. If I want each of them to have a custom glam and I also want to be able to switch between classes anywhere, I need each class to have its own set of gear. Which is hard to do with Unique. Not saying Unique is the thing that needs to go away to solve this (changes to Glam would be more ideal, but seem less likely), but it is exacerbating the issue.