What's the one oversight that stuck most with you?

[Powerogue]

"The first location we will visit is the Dark Portal in the Blasted Lands. It was there that Gul'dan used a piece of the Vision of Time to travel between realities."

I can stitch a plausible head canon together on that one.

The plan was, most likely, summon Archimonde, conquer Draenor, then tune the portal to Azeroth and conquer that too, using said shard that they got their hands on (let's say they found it on Garrosh's corpse). Archimonde, in dying, hastens that plan, casting the spell, using the shard that was on Gul'dan, to hurl just him to Azeroth. Then, after we kill Gul'dan, we find that same shard on him, and that's then used as the catalyst for us to return to Draenor the 20-ish years later.

Again, stuff that should have been in-game, but no retconning was needed to get there.

[Grazrug]

Draenor the red world not being red at all in WoD

It turned red after gul'dan castet the spell to slowly kill off the planet and cutting orcs off from the spirits.

[Jastall]

Oh boy you're blind.

Azerite is being used everywhere for everything. Did you not pay attention to any of the quests? The dungeons?

By enemies, yes.

The factions who went to war over the stuff barely ever use it however, and the PC hardly counts since we're funneling all the Azerite we get to the neck regardless. That changed a bit in 8.1 where the new War Campaign and Assaults show it being used, but aside from one Horde-only quest it does nothing that other sources of power don't seem able to accomplish.

[Terongor]

Then Saurfang should've spearheaded the Lordearon defense.

Well sylvanas had over hunred years of experience as saurfang have had only about 40 years. Also Sylvanas was the leader of the elven military over hundred years and saurfang at best was second in command so no sylvanases experience is still longer tham saurfangs.

[Ujimasa Hojo]

Who could forget that Kurdran debacle in the Council of Three Hammers? Red shirt guy became immortalized as an NPC and Blizzard "corrected their mistake" by making a short story centered around it.