I like the mod slot idea but those perks would be totally useless outside of the raid, which wouldn't feel like much of a reward. "Congratulations now you'll have an easier time beating this activity you already conquered and have most of the gear for" lol. On the other hand if the normal version of the raid dropped that sort of thing, to prepare you for hard mode, and the hard version dropped stuff useful in any PvE activity (like I mentioned) then we might be onto something. High five?