I sometimes think about bringing back avatar. I was one of the avatar ops, and came up with the idea of the afterlife, which was intended to improve its single player playability, but my version (navatar) was maybe a bit too sprawling and ambitious.
In case you take it up as a retirement project: what I'd love to see is an avatar builder's kit. Create the core engine, a basic level, monster, item, and class editor, and let people mod it. The basic party mechanics and att/def model could be standardized, but let people create their own game based on their own data. Create the hooks for people to add additional gameplay (ingredients, etc). Let people self-host.
Like you, I think about doing this every couple years. :)