I want to see action-based gameplay, preferably a bit more involved than we saw so far. I wouldn’t mind spells to have more synergy (things like reducing each other cooldowns, stacking up energy meter, or dealing more damage if cast in sequence).
I hope that the gameplay of Diablo 3 will be taken as a base and improved. Unlike some people here, I hope that as few Diablo 2 elements appear in D4 as possible - second part was a great game… 20 years ago. I would not even pick it off the shelf today.
I don’t need any “Role playing” - as in choices and so on. I’m completely fine with a completely linear story.
Only, I would ask Blizzard to hire a competent writer. I know, I know, a man can dream. Just look at Wolcen that manages to deliver a solid feel and solid plot without doing ANYTHING special and without Disney-grade drama.
We really, REALLY need just a solid dark fantasy plot, and not the cartoonish stuff Blizzard is making across all of their franchises for years now.
The only non-linear thing that I would’ve loved, is for each class, or possibly even each class-gender combo to have a separate side-story that you explore during campaign. Think of Divinity 2 - different NPC can be involved in some character’s storyline and offer different dialogue, even though the main narration remains the same.
I think that’d be cool.
But choices? Branching plot? Nah, I don’t think Diablo needs that.
One of my main concerns about D4 keeps being always-multiplayer thing. NOTE: I’m explicitly not asking for offline mode. Keep your online DRM. I want to have Private mode where I only ever see players that I explicitly invited. No random people - not in town, not anywhere.
That said, a mode that turns off all social features (like auction) and only leaves direct trade with people who were there when you picked up an item - is another great thing that I would welcome.
Lastly, I want to see Diablo 4 to be its own game. To not try and DESPERATELY mimic Diablo 2 in all places because of how afraid the devs are of their own fanbase.
Sadly, so far, I see that it’s copying a lot of stuff from D2 in hopes of appeasing the community of 20 years ago.