Before I start with the suggestion I will just point out that I am not max lvl yet, nor necessarily know much about exotics or the gear later on the game, but here it goes:
I think for a game like Guild Wars 2 that doesn’t focus on the gear-treadmill grind other MMORPGs does, that we could at least get a feature like the unidentified dye, but only with skins (an armor piece with no stats that could be transmuted to a fitting piece of armor). And that they could be only founded very rarely in world, but biggest chance in Dynamic events / Dungeon for example.
Just something that I thought off. Peace :-)