Is there another time and place in Warhammer lore besides the end times that would be cool to adapt to a tide game?
I like waves of rats and nurgle enemies, but I’m curious about a more flavorful experience involving more locations or more enemy types. I don’t know if that could or would happen, but it’s a thought.
You can pick almost any time line and have the same general scenario.
Be it the The Old World setting, the Great War against Chaos, any of the major Greenskins invasions into the Empire, the Red Plague, Goblin Wars or the Vampire Wars.
There are times and places for tide games in Warhammer.
One thing that could be an alternative could be fighting around an attempt by the Dwarves, with some non-Dwarf allies, to recapture a hold from the Greenskins or the Skaven.
That would be awesome. Basically Vermintide with only dwarves and only dwarven maps. I would buy it in a heartbeat. 
And the many unrecorded tides where the victims largely died.
Problem with a Dwarf only tide game is that it’s quite limited tbh, like Bardin already has what, 75% of all weapons Battlefantasy has given to Dwarfs in lore.
Having 1 or maybe 2 new Dwarf character in their own games (Hedda Bardinsdottir when 
) with their own twist on how they make it work, while having other characters leaning on different factions or origin to make different things:
And many more, even inside the Empire or other previously used factions.
Tide wise, it’s more about what they’ll want to do than when, as for the most case each factions that would work for a tide either have had many hordes that went against other factions (Mainly Chaos, Greenskins, Skaven, the whole Undeads…) or have acted as a tide as a defensive strategy (Tomb King, Lizardmen…)
Ideally for a Battle Fantasy, I’d hope for either Lizardmen with player side being Chaos Warrior raiding, or a tide set around the Dreadfleet novel (Vamp. Coast; Vamp. Count; Undead Skaven; Tomb King; and Chaos Dwarf Mercs), with the player acting as member of the Grand Alliance
Having a dwarf game could work if they make the use of the weapons more unique with different talents. You could have different move-sets for the same kind of weapon per character, or if there were a feature like being able to choose a combat style. Could even include non-dwarf allies.
Greentides and Skaventides, I could see it working. That said I’d like a team up, and it’d be neat to have custom character creation like Darktide, so maybe it’s team up scenario where heroes are sent on missions. More kinds of tides and enemies would make me happy; adventures to more locations. Don’t know how feasible that is. More likely if not the end times, I suspect it’ll be themed around a more specific time/place with a specific type of enemy in mind.
I thought I mentioned in my post that there wouldn’t only be Dwarfs but also non-Dwarf allies who would help the Dwarfs in their quest to reclaim a hold in the scenario I suggested? Thus allowing for non-Dwarf characters.
Anyway, regarding wizards I would say this. If we add Amber Wizard then shapeshifting is a must. Summon animal spirits might be something for a Warrior Priest of Taal or something but for a Beast Mage there have to be shapeshifting. Maybe it could be their ult that they transform for a brief period into a man-beast hybrid with massive boosts to its stats?
EDITED: Also I would suggest custom characters. The Ü5 are great but with there would be no end to the possibilities of careers if custom characters were introduced.