Second chance at campaign side content

Right now if you skip a side quest or piece of side content, you can lose out on permanent buffs that can only be obtained by going back and clearing them while being far too high level trying to fill your character out in endgame.

I think a simple solution to this is simply letting endgame bosses give the same rewards. Most campaign zone bosses have been reworked into some endgame map boss. I think that if you kill the endgame map boss that mirrors a campaign boss that gave one off content, and you skipped that campaign boss, you should get the bonus reward. So the two skill points, permanent cold resist buff or quest drop for chaos trial and other trials. Ideally also things for like, Burrower, from act 1 where while it's not technically the boss that gives the perma-buff, you need to kill the boss to complete a quest that gives 2 skill points.

This could be represented on the world map similar to how the pantheon thing was displayed in 2. A map with a boss mod that would give you a permanent buff you are missing glows and tells you what you gain if you hover it. If a zone is the right zone but is missing the boss mod it shows a greyed out boss icon. If you hover it, it says what you would gain if you added a boss here. Assuming this UI goes away when it isn't needed because you already have the perma-buff it would change literally nothing for people that full clear the campaign. But it would easily allow players that don't reach end game to access that content at their difficulty level for the same reward. Instead of having to port back to campaign and just pub stomp everything for a mandatory upgrade. Which feels super boring.