I'd rather see Larian end this and start work on a new story that takes place some 50 or 100 years down the road where many things in the world can be changed and become totally new.
This would be a very interesting thought, and parhaps something for the future.
But : Since most (if not all) role-playing games evolve around "war" as the theme in which a "hero" develops, this is unlikely.
Actually, I can't remember ANY role-playing gme without "war" as the major theme !
So, I tend to rather expect that Larian would rather exploit the recurring theme of War Aginst The Damned One even further. I believe, this war needs an epic conclusion ! Because there's still the Black Ring ...
Apart from that : As I wrote above, I'd personally like something like Gothic 3, only in Rivellon.
I' lik to see some pretty normal, not war-torn towns and enclaves, too. Something where the action stops at, something to rest in. So to say.
But that ll is Larian's decision. All Divinity games have been rather action-oriented games in the past.
And that, although they do know to do non-action game, too ...
When you find a big kettle of crazy, it's best not to stir it. --Dilbert cartoon
"Interplay.some zombiefied unlife thing going on there" - skavenhorde at RPGWatch
