Everyone else is trying to be neutral on what province you can join. I'm here to advertise for Iliac Bay! We're in the process of spooling up an interiors department and would love to be able to get you making dungeons in our prerelease areas!
That's the LOD mesh for the worldspace. You'll need to regenerate it. https://www.darkcreations.org/hoddminir/generating-lods-for-your-worldspace If you're only looking to get rid of the stuff in the way for now instead of proper terrain textures/etc., you can skip ahead to "Continue to generate the landscape LODs with Oscape".
I'll get the thread going as soon as I can; busy week. Any particular interiors tileset you prefer? It'll be pretty freeform. You build a dungeon or whatever you like, and I'll help out with fine-tuning and details. If you haven't, I highly recommend the Creation Kit Wiki's introduction tutorial.
Hello! I think our needs will soon be focused on interior/dungeon design for Iliac Bay, so I'm aiming to build up a larger department for that. I'm willing to guide you through with building a basic dungeon/interior.
Essentially, unless we made something that totally goes beyond our scope as a quest/land mod, the extent of 'being emperor' is a neat little cutscene where someone calls you emperor. Only reason canon can get away with stuff like making the Champion of Cyrodiil into Sheogorath is because of how screwy that position is. Sadly, Emperorship is less similar to the role of Sheogorath than I would like.