I really liked RAWR, I think it was superior in helping choose optimal gear, just in the way it presented information and allowed users to swap between gear and see how it affected all your other gear. For tanks especially it showed mitigation, survivability, and threat on each piece.
I haven't created addons before but am very interested in learning so I can tackle this project. It was originally on codeplex and Elitest Jerks but both sites are gone. I have the old TBC and WotLK versions as well as a download of the archive on Codeplex. The original authors have been inactive for years.
Any help or direction would be greatly appreciated.
EDIT: This would be used for classic WoW and TBC and then in the future WotLK if it is rereleased.