I think the simplest answer is that the game-building technology is better now. The Dwemer ruins in Morrowind looked very sparse compared to those in Skyrim... I think the devs just have finally got the technology to really bring their vision to it's proper form.
For a more lore-friendly explanation, it could be that skyrim has much better stone for them to carve their homes out of. If I remember correctly, the Morrowind ruins were mostly metallic in construction... Could be that the stone around red mountain just wasn't suited to carving vast halls into.
For a more lore-friendly explanation, it could be that skyrim has much better stone for them to carve their homes out of. If I remember correctly, the Morrowind ruins were mostly metallic in construction... Could be that the stone around red mountain just wasn't suited to carving vast halls into.
Actually, there's a book in Skyrim that remarks the Dwemer utilized different designs and construction techniques based on region and family influence.