Diablo IV post campaign exploring and doing lots of side quests and areas I never got to doing during the campaign since you are meant to focus on it or you will over level doing the side quests (it is a huge campaign with tons of stuff to do). Sanctuary is gigantic, Necromancer level 47, and only still in second region of Scosglen.
Nearly all gear is legendary now, once at level 50 will do Capstone Dungeon and World Tier 3. Drawback of Diablo IV necromancer is undead army minion max number is even with upgrades still very, very limited in comparison to Grim Dawn necromancer, Last Epoch necromancer or Path of Exile necromancers who can get absolutely cool insane shit like Vaal Summon a Entire Skeleton Army.
Vessel of Hatred Expansion looks cool, but Path of Exile 2 just looks absolutely bonkers on a entire different level.
Grim Dawn Fangs of Askerten Expansion apparently pushed back to 2025. I would not be surprised if it actually is Grim Dawn 2 given its apperently massive size and overhaul. Also the complete lack of footage which could be hiding a new engine...