Idea: Integrate the final acts into the end game mapping

A lot of people have said "End game" is the problem with this game.
I see a lot of opportunities to actually take the current acts, the lore and storyline,
and integrate the continuation of these acts after actually doing a bunch of maps in "end-game".
Like I actually don't mind the interludes for taking us to 64-65 and into maps.
To me it would feel natural to go into maps build strength, explore the world of wraeclast for specific events and items that you need to unlock the final acts. And ofcourse just the concept of time passing.
I would put ACT5 after level 80. And ACT6 after level 90.
But probably put them behind a currency that is left behind by map bosses or league related mechanics that are often in the map. And once you have a 100 of them. You can open the ACT 5 portal, and maybe the ACT6 portal would be from 5 to 10 pinnacle boss currency drops.
These acts could be combined with some much better gear drops, higher currency rates from the bosses and mobs in there and much more epic fights/maps. I mean after arbiter there is an animation there already. And after act 6 you could probably unlock exceptionally hard pinnacle bosses/concepts that really would push players to continue playing into those upper levels. And to me it would feel like a natural progressive path into "endgame". And these acts would then feel "earned".