I feel like you need to be introduced to mods. There are...a lot. Even if you keep it to just relatively high quality ones that add content (rather than mechanical overhauls or graphical overhauls), there are still a lot.

I'd suggest Falskaar, Wyrmstooth, The Hanging Gardens, The Maelstrom and vicn's mods (Vigilant, Glenmoril and Unslaad) as a starting point.

Actually, that's not true, I'd recommend Legacy of the Dragonborn as a starting point, then grab mods that require it and mods that require those until you have all the content mods that can have displays in the museum (which includes all the ones I mentioned before, but is not limited to them).