I like the idea. I think the set bonus perk should be switched up just like any other perk, hence making the grind longer and giving a reason to play more. Take New Monarchy armor for instance: Chest: sprint delay reduction. Arms: radar always on Boots: sprint delay reduction Helm: sprint delay reduction The bonus would not activate until you get the arms with sprint delay reduction as well, thus making you actually play more to get that piece of armor to complete the set. Plus this way you can pair the set perk with an artifact perk, combining the two for your ultimate play style.