Mmmhmmm. Just imagine every few hours the game updated boosts to (for example) specific dungeons. If one has been popular then the nect interval you have a -10% loot and xp (number taken out if my arse). And these numbers posted clearly in and out of game. I think it wouldn't take too long before minmaxers have identified breakpoints for when each dungeon is "profitable". And not too long after that evegy dungeon would be about as profitable as every other.
I wouldn't mind at least trying such a system. Think it would be neat.
Something I have found immensely useful is the filter on the activity panel, top-right of it. Being able to easily highlight for eample abilities that does something with vulnerability gives me so much better overview. Really helps me determine where to put the points when I'm too lazy to tab to a guide.
Aöso Fextralife have a bunch of build guides.