Well destiny has RPG elements, so why not take sets into consideration? if i'm wearing let's say full dead orbit gear, why not give me a discount and more dead orbit exp, maybe a unique bonus for the faction? if i'm wearing full specific raidgear, why not give me a(reasonable) bonus to the enemies in it or even a damage reduction if i'm using the aegis? (in case of the vault of glass) if i had weapons that fit to my equipment why not give me extra-ammo or a basic range/recoil/whatever bonus? more stats, lifeleech, speed, better loot chances, more glimmer, certain abilites work different, let me look shiny, grenade-explosion on death, heck small shockwave if i land from a high place (still taking damage...maybe)..sure they would be hard to balance in pvp, but there you could just straightup disable them the options are basicly endless and i'm sure people here have some even better ideas than i do. (yeah i know i suck at english, try adding that after your comment, not instead of one)