I like this idea, but technically we can do most of this already by equipping lower power gear and set the limit for ourselves. A lot of those players that want a challenge also refuse to let go of their most powerful builds and run something "off-meta" or lower power to handicap themselves. It would be far better to set the level of challenge we want for ourselves and at the same time decrease or increase the rewards given for completion of those activities. On that note, we're on the same page I believe but of course it is up to Bungie to either implement some sort of course correction as suggested or let the ship sink.