I was looking at some concept art of Morrowind and I thought. If only Morrowind were really that big. Here's the concept are if you want:
http://fc06.deviantart.net/fs71/i/2012/111/2/d/telvanni_tower_by_lelek1980-d4x2dx3.jpg
http://fc09.deviantart.net/fs70/i/2012/176/8/1/the_caravan_by_lelek1980-d54t6s2.jpg
http://fc08.deviantart.net/fs70/i/2012/083/e/4/balmora__aerial_view_by_lelek1980-d4to7sw.jpg
http://fc08.deviantart.net/fs71/i/2011/343/8/0/red_mountain_by_lelek1980-d4if2nx.jpg

Imagine if it took a whole hour of real life time to travel from Seyda Neen to Balmora. That would be absolutely awesome! It would take a lot of modding if it were to be added though.

I actually made a post about this quite some time ago, and frankly, this is the top mod idea I'd like to see put into action. But it'd require a lot of work, which unfortunately, not many are willing to do. Of course, I'd join a team, if one formed to make this idea come true.

Well it'd take a while just to do Balmora itself, I'd definitely join! I've been tossing this idea around a bit and thought how stupid the Red Mountain would seem. It would be much wider than it is tall because of the limit thing of how tall land can go. It could work though. We would have to start with the small areas first. The wilderness type areas would be a good start. Smaller towns and stuff like that. Seyda Neen would be about the size of Balmora. I have no idea how we would get Vivec to work. Just brainstorming.

I could imagine that the FPS would be insanely low if we had such a world to play around in

Although I love the concept art. I use em myself as Main Menu replacer / Splashscreens.

Depends on how you set it up. I got highly clustered areas with decent-to-good fps!

The concept art is beautiful, but it seems like a huge task. Let's say you increase the size of Vvardenfell 10x. That would mean adding on the order of 10,000 new interior cells and 24,000 new NPCs, and to make it all seem lively, you'd probably want to add a bunch of new dialogue and side quests.

As i said, it would be a huge undertaking lol.