I’d expand on their Gladiators Sanctum and make it a self contained island.
Then make PvP either F2P or attached to the Xbox Game Pass.
Get an influx of players who wouldn’t normally play WoW. Maybe after getting hooked, they’d pay to access PvE.
Level 1-20 is clearly not enough of a drawcard.
PvP is a small part of the game, Blizzard spends the least amount of money possible on it already.
If it was a path for them to draw in new players, it might receive a budget boost.