As someone who has played TES 3-5 I can honestly say there are some places more than others that I want to explore. For instance we never really saw kavatch or winterhold as they were ether completely or mostly destroyed. Also checking Morrowinds mainland more. And the other provinces. I have to say skyrim is the one I want to see the least because it was the most recent.

Black marsh is my most expected land, it holds myy favorite race and quite a few other weird things. But tbh I'm not as hyped as I'd be for a BM crafted by BGS, I expect a pretty generic looking setting.

I cannot wait to see the Summerset Isles and Valenwood, especially the Giant trees in the forests and Summerset's Capital.