So I’m a heavy MMO influenced person, and what I would love to see would be a scaling difficulty. Let me elaborate.
In Diablo as an example, you got Greater Rifs; Maps which increases the difficulty infinitely. You could make leaderboards and scaling rewards based on the +level you did a certain map on, this would help out with the endgame “issue” which some people may find themselves in now.
It would require some work on your end though, but when the scalingtech is done, you got a great gamemechanic!