Having just completed the building of my Tel Uvirith stronghold, I wanted to make a few suggestions.
I am using Dave Humphries Furniture Stores and the Weapons Rotate mods. I am also using Emma's Travel Agency mod, which transports you and any companions to various areas of Vvardenfell, including the strongholds. Between these three I have found that Tel Uvirith, given all the underground space, can be made extremely functional and habitable (without a huge amount of effort), probably more so than the other two strongholds.
I have essentially made the foyer into a display area (using bookshelves and weapon racks), added bookshelves to the Lower Tower area with the two beds (it will become a library/lounge), and added a bookshelf, along with a some chests/small storage boxes, to the study/alchemy room (the first room you enter when going into the Upper Tower). I have also added chests and shelving to the Dungeon.
I don't know if you are looking for layout ideas, but if so I can post some screenshots once I have it all set up, it works quite well.
btw, you might want to lighten up your screenies
I have found that the easiest way to achieve this is to take the screenshots while wearing an item that provides Night Eye or Light.
Another suggestion I have would be to do something about the Dwemer-made "servant" that rolls around in the entranceway. It frequently either gets stuck or completely blocks the narrow passages.
I am tempted to "evict" the damn thing, but for now I'm just opening up the console and using the "RA" command.