Endgame idea - Tower overhaul

For Towers, they should make the mechanic the inverse ;

Instead of clearing a tower to juice other maps around it, make the tower an unlockable area by clearing maps around it. The more maps you clear, the more the tower is close to be unlocked. Afterwards, when you clear the tower, it refreshes maps around it for them to be cleared again, and if you do so, the tower gets another time unlocked for another possible clear, but this time, harder. What it would bring is the dungeon-like experience where the more you invest in it, the more the tower is rewarding and feels like a dungeon crawling type of gameplay. We could have instead of corrupted towers, some kind of abyss descent ''towers'' where instead of climbing your way up the tower, you just grind your way down.

2 thematics, simpler mechanic, more rewarding and satisfying tower clear. Imagine Diablo 1 but as tower. Each stage is unlocked by clearing maps around it. There would be maps used for the ''climbing towers'' and others specifically for the dungeon-crawling type of towers. For example, abyss(dungeon), hidden grotto(dungeon), mud burrow(dungeon)... The towers would be like a sustain-type of map where you get better rewards by clearing more stages.

I always imagined D2 making an update around Uber Tristram to bring more flavor, where after killing the trio, you get to unlock the Church from Diablo 1 and face a new type of challenge. It would involve another type of mechanic where people are forced to create new kind of builds around it. Usually, sustain during lategame isn't a priority, it's more about taking out your enemies before they reach you. But as you would crawl down this dungeon, no portals would be permitted, a special stash could only be used to drop your items instead of pulling yours out of it, and so you would need an incredible amount of sustain to get through it without dying, and monster diversity would be more focused around less density, more individual power for each of them, helping the player have a more engaging combat and less cluttered screen of visual effect.