IMO, anything to do with RNG is gonna be unfair to someone at some point. You can run these things 1000 times putting in maximum effort and not get your drop while someone who comes in and does nothing but auto attack gets their drop first run. Doesn't feel good.

There are a couple of systems I really enjoyed and they come from, go figure, FFXI.

The first is walk of echoes and other content that did similar things, a system that rewarded you with items based on your personal contribution, the more effort you put in, the more rewards you got at the end. There was still an element of RNG involved as you still might not get your rare drop the first time but you got more out of it than someone who came in and did nothing.

The second is a more recent content called ambuscade. Every time you run it you are rewarded with a special currency called hallmarks, whenever you reached a certain plateau of total hallmarks you got a piece of gear (new set every month) so once you reached 14,500 hallmarks you had the full set for that month.

I think some kind of combination of the two would be a great loot system. Awarding you with currency at the end of a run based on your contribution would strike a great middle ground between having you run it multiple times a week and getting the loot you want in a reasonable amount of time.

Essentially similar to capped weekly tomestones but rewarding you with gear specific to that content, unlike tomestones which are more general.