What you would have to do.

[Encryptions]

If you want a tank class to be a tank class then you will have to change a lot in pve and right now you can't make this work due to the damage reflect mobs and suicide bombers. It can be possible in the level 86 expansion though.
So if you want tanks to be tanks then you will have to remove all healing effects on rogs and mages in the new maps, only allowing warriors horn to heal them. You have to boost the mobs hp by a ton and at the same time decrease their damage so they can't just 3 hit rogs or mages. It should take maybe 15 hits for a rog / mage to die. This gives the warrior time to think and heal, works for new players and older players.
Problem: warriors want pve kills, why run a map if it doesn't benefit your character? It will also result in being an extremely long and boring map to play. AL is about sitting in 1 spot attacking mobs and spamming skills until the mob is dead, there isn't much to dodging attacks since most of the attacks are not dodge able.
Thats 1 major flaw as to why its boring.
-Edit. It does have many options to make it not boring such as: a great reward at the end or crafting mats to craft 86 mythic gears, house items, make it where 1 kill gives all 4 in the map 1 kill towards pve, and more. All 3 classes are used, rog for dps, mage for mana healing, warrior for hp healing.
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