Scars of Velious also had content that never made it into the game, though not much it seems. Most obvious were new versions of centaurs and burynai to match the cold environment. There are only a few sketches and screenshots floating around the internet of them though. Who knows if any zones were originally intended to be designed for either.
https://m.gameswelt.de/everquest-the-scars-of-velious/screenshots
http://www.cdaccess.com/gifs/screen/everqusv2.jpg