Feedback on mmo-ish open world part:
I worry that the Diablo 4 open world will be as dead as it is in retail wow - since it will probably be cross-realm scaling sharding phasing garbage - no integrity leads to no social interactions (you will never meet the same people again, so no one cares).
I can understand that some Diablo-franchise fans want that solo gameplay, but since Blizzard announced Diablo 4 as an mmo, which I personally am really excited about - it will either be a good mmo, which genre-wise must mainly rely on strong social aspect (as vanilla wow was and classic wow is now - with realm communities, famous realm players, random outdoor meetings which may lead to a relationships, etc.), or a semi-mmo/semi-single abomination with a sharding open world where interactions between players don’t matter (as retail wow, destiny). I would guess, the developers enjoyed the mmo-part of testing the zone because they kinda know each other already, and they probably did it via single realm that could fit their team - meeting each other from time to time, collaborating on dungeons/events, doing pvp - it’s like a server of friends (you could see something similar during the streams of classic wow closed beta on Twitch). But they have to create an environment for a complete strangers to develop such bond between them.
The other thing is - if they implement any automatized “convenience”-systems like dungeon finder, I hope there won’t be a thing when you press a “ready”-button and teleport to a dungeon or a world event from any place in the world, which kills the meaning of travel and devalues the world’s size and danger.
A question (a suggestion?) for the future: will you be able to rotate a camera somehow? Maybe choose a direction of it, or an angle (at least off-combat?), like it was in the cutscene from the Blizzcon demo, so you can see a landscape and decide which way you want to go, which visible object to explore?