First of all, please fix the exploits and cheesy strats, because they’re ruining the idea of fair playing field.
Temple of Sethraliss exploit: clearing up to last boss on mythic0 and retaining the mega haste buff after starting the keystone.
Freehold exploit: you already fixed cheesing the infested to not spawn by tagging him through the barrier. What about the exploit allowing groups to skip pig catching or even the turtle miniboss.
Siege of Boralus exploit / cheese: being allowed to kill tentacles on the last boss with the spotter, bonus point for bolstering week buffing your spotter to kill stuff faster. Spotter was meant to help kill trash, but it wasn’t affecting big trash like horsemen. Why does it affect parts of a boss encounter then? That seems more serious mob than horsemen.
When you fix these exploits, then you can look into adjusting difficulty of these dungeons for people who don’t use exploits, so have it much harder now to complete them. For example an average group can easily get overran by multiple tentacles on the last boss in Siege, it takes so long to clean them up.
Another thing mentioned already is stuff pulling through solid walls and floors with azerite traits like laser matrix or frostwhelp indignation, or class abilities like special delivery, halo or frostwyrm fury. Makes dungeons like waycrest and tol dagor much more frustrating and unfriendly to specific classes that put your group at risk of ninjapulling through solid walls and wiping, so you rather not take them.
Hitbox of Aqua’sirr in Shrine is also way too big and you have to meticulously clear every trash in 40 yard radius before you pull the boss if you have a fire mage or similar class with uncontrollable cleave. Being able to pull Heldis miniboss from miles away is just silly.
Also I wish doing dungeons “the normal way” instead of shrouding, death-skipping or wall jumping around mobs was less punishing, these strats very often backfire in pugs, but when they’re deemed so much better than just killing the trash (due to that trash being overtuned or natural path through the dungeon severely overcapping your trash count %) it creates unnecessary drama.
Props to you for nerfing entry underrot trash, that was one good example of making clearing the trash more viable than “always skip”.
There are several “always skip” places especially in Atal’dazar, Freehold and Motherlode - I’d look into that trash and ask yourselves “why is everyone skipping it”?
Many other issues were already mentioned, for example high unavoidable damage that scaled indefinitely on high keys instead of capping at specific player hp %, things like spit gold on King’s Rest 1st boss. Haven’t we learnt anything from Legion tyrannical Hyrja and Lady Hatecoil?
Also in my personal opinion tyranical / fortified should be removed and some lesser version of it incorporated into basic keystone scaling. Otherwise things become impossible to balance, becoming either pushover without the corresponding affix, or to tedious to go through with the affix.