-Soloable BFA content,especially raids,warfronts.
It should be enough to do the Legendary Cloak questline once, after which the other characters could have a skip option.
-A similar option for N’Zoth assaults in Pandaria.
-BFA Timewalking. 2 new mounts (horde+alliance version) and a boa rep token that can be bought for each faction.
-SL Timewalking ?
If TW comes out every 2 years, then it would be time for this as well.
-New spawntimer for Rhuv and Konthrogz rares.
When the expansion was still active, it was easy to find in the custom group, but now it’s almost impossible, and these two have the stupidest spawn.
-SL: A small buff for extremely rare quests like “Putting A Plan Together”.
Anyone who has the mount knows what it was like back then.
-SL: Protoform Synthesis rare material drop chance buff.
I grinded out this part afterwards and it was still terrible. Most of the materials have a very small drop rate and some have only one chance per week.
That’s all I could think of now, focusing more on the old content.