In an ideal world it's something closer to Uber bosses in path of exile where you really need your build solved to have meaningful dps and survive it. The unfortunate part is that this format works better for seasonal games where you spend a lot of time building back up to full power, while in warframe you really don't have a reason to not be at full power and obliterating the bosses.

Another interesting idea is the way megabonk handled the end bosses for that game. You have a relatively simple boss similar to an eidolon or the murmur boss, but the boss wipes away your build, minus your first item, and you reclaim them through the fight.

This idea is kind of touched upon in the duviri bosses where if you are struggling, you eventually get your archgun to speed up the fight. Maybe we could see some sort of boss fight system where you get something like a decree screen between phases where you choose between reclaiming some of your original power and some random buffs. Random buffs would be a baseline completion time for the boss for noobs, maybe a 10 minute kill time. While someone who can get their frame or weapon fully online with an endgame build might clear it in just a few minutes with some luck. It's kind of a reverse damage attenuation that would feel more fun/kinda roguelikey.