Hi ttomas. There is no where near enough infromation in your post to make any reccomendation. Sorry.

Sounds like you are well experienced with bike building though. I think that my approach would be to start with road tires on the Stumpjumper, and then play with different bars and configurations until you have a good idea what works for you with whatever your current medical state is, the type of riding you now prefer, and the utilitarian needs of your life. Once you have played with these factors enough you should have enough information to build something to suit both what you need and what you want.

Building something I like out of found materials is kind of what I do with bikes. I have several bike that started out kinda meh, but are now bikes I truly like and would have a hard time selling. Who knows, you may even find your next calling.