I'd be totally down for some armor set buffs or benefits. Especially from the factions/raids/ or special events. Maybe even have multiple sets and put faction rank requirements on them so that you'd know just from looking at someone how invested they are in each faction. Seeing a mix of guardians with Tier One, Tier Two and Tier Three Iron Banner/Dead Orbit/Queen's Wrath/New Monarchy/Vanguard/Future War Cult/Osiris gear would be pretty neat. I think it would also help with Clan identities and fashion whenever they fully implement them into the game. As long as there was still reason enough to mix and match armors for those who like to be unique.