A few issues with Vengeance that are worth pointing out. Context matters here, so this is in the context of the other campaigns being removed and players only having a choice between Grey Host and Vengeance. Since this seems to be "permanent" (noting "we might turn on other campaigns from time to time if necessary" was the gist of the explanation), then Vengeance is the replacement for the other campaigns.
First, AP earned in Vengeance does not seem to be counting for Alliance War rank after exiting. I just earned 25K AP in Vengeance which should have been enough to push that character up to Rank 5 (Tyro, Grade 1). This did not happen and they are at the same Alliance War rank (Recruit, Grade 2) they had before entering. Additionally, 25K AP should have been enough to generate a Rewards for the Worthy coffer, which did not materialize, either.
Second, antiquity leads can drop in Vengeance (got the Ayleid King skull lead in a delve), but the Antiquarian Eye cannot be slotted in Vengeance. Good luck getting into pop-locked Grey Host to follow up on that lead.
Third, PvE "discoverable" locations (Wenyandawik, for example) are not discovered even when standing right on top of them. There's nothing which needs to be done for that particular location (it shows "Quest Hub" on the map, though), but it remains undiscovered. Mundus Stones cannot be discovered, either, and interacting with them just produces a "not enabled in Vengeance" message.
Fourth, resource nodes visually spawn as Level 1 nodes (Iron, Jute, and Maple) and drop CP150 resources (Rubedite, Ancestor Silk, and Ruby Ash), but neither of those align with the character's level or crafting passives.
This is not a slam at Vengeance (there are other threads on other forums for that particular discussion) as much as it is to point out that if Vengeance is supposed to be the replacement for all the other campaigns, then it needs to have the appropriate functionality of the other campaigns. "The devil is in the details," as the old adage goes, and the details have been left behind in the desire to push out Vengeance.
I'm fresh out of outrage, but I could muster up some amused annoyance if required.