A new entry (basically a reboot) . With all of the characters coming back. Anyone who was a pallet swap would have traits that separate them.
i.e. Diablo and Sauron would look different form each other. Here is an example of Diablo’s look me and Jeffron27 had in mind.
Also the return of all of 7 original gods plus Slashfang and Necrosan as a final boss. and of course, New gods to play instead of the humans.
Finishers would be called extinctions like an PRII
Characters designs would be recognizable but up to date.
Faster gameplay
changes in gameplay that kept a few people form wanting to play it in the 90’s.
Also here are renders of the Diablo Model