One of my since-buried threads was about having High Rock as expansion material. Everyone loves expansions, and it's really the only fitting place to choose based on a number of factors. I'd love to see High Rock, personally. It'd fit well, and for once I'd like to go between provinces in a single game. We have already seen High Rock through Daggerfall, but I think that gaming has evolved more than enough to provide a completely new experience. I don't think anything made now can compare to a game that old experience-wise. And given that it has to scale with Skyrim, it'd be not only much smaller than the game Daggerfall, but about the same size relative to Skyrim as Shivering Isles was to Oblivion and Bloodmoon was to Morrowind. It just has more cities than both of them combined...
Yeah, that's the biggest issues. Despite being apretty small place (relative to Skyrim, I know they can be any size Beth chooses in it's own game!) it still has 8 cities in it, and undoubtedly many towns. All of Daggerfall would be too much. Having the Iliac Bay region might work, or maybe that bay at the top that leads into Orsinium, and have some good reason why we can only go to a small region of this province. Maybe have Orsinium be it's own 'hold' or similar now.