Hand crafted maps that stay filled in that are *meant* for exploring.
Day/night Cycle with weather
Verticality and height when exploring.
Camera rotation
Combo and multiclass for tons of different options when creating character.
Factions with reputation, enemies that attack each other and not just 'sit' there
Legitimate enviornmental story telling
Fairly heavy actual 'RPG' elements in both quests and stats

Honestly, none of this sounds out of the ordinary and many arpgs have some, but I'm not sure any have them all in one package.

Personally feels and looks a bit like a mash up of Diablo and Divinity Original Sin series mixed into an arpg where the map, story and 'exploration' isn't just there to get you from one point to another so you can rush to endgame.

My biggest issue/complaint so far is there are just so many damage options for you to worry about on both defense and offense that its a bit overwhelming and convoluted (at best). Over time this is getting better, but man like 12 something damage types to wonder about when picking up gear and fighting enemies might just be a bit too much lol.

So far, it all adds up to some of the most fun I've had since Diablo 2/D2 Remastered and if you like more traditional RPGs, this leans on that side MUCH more than any arpg I can remember playing maybe ever.

Lastly, as a Necromancer/pet/summon player in almost all of these games, this is one of the most fun versions I've had since Diablo 2 and the pets actually hold their own in this one, making summon builds feel better than about 99% of any arpg out there now that tries them.