I'd be fine with whatever setting they chose, and basically whatever combat/levelling mechanics. What I want is an actual story, with actual characters and dialogues this time. The joke they have in place of these very important parts of an RPG in all their latest games won't cut it anymore. In order to achieve this, they probably would have to replace their whole writing team (well, maybe apart from some of the people responsible for the lore; the lore is quite good) with new talents. I mean, after Morrowind all these aspects went steadily downhill in all their subsequent games. Already in Skyrim I'd say that dialogue, characters and story (both the main story and the side-stories) are not that much above atrocious levels, and Fallout 4 is a complete joke with its four dialogue "options" (I can't even call Fallout 4 an RPG in my right mind).
Sadly, my gut tells me that they will go even further downhill in the future instead of improving, so I don't really have any hopes for TESVI.