Hi and welcome to the forum -
Can't help you with restaurants but, very kindly, what ARE you interested in seeing in Rome if not art, churches, ruins, views of the city? Have you ever been there before? The historic center is plenty authentic: let's just say that most of the things visitors go to see weren't originally created for tourism, and it isn't devoid of "real" Romans/Italians,
Are you OK with museums as long as they're not art museums?
You might enjoy a walk on the Appia Antica but much of what makes it very interesting are the ruins of funeral monuments, a circus, a bath, catacombs, etc. along the way. There are aqueducts in another of its sections.
https://www.parcoappiaantica.it
Yep, you might enjoy Cimitero Acattolico (non Catholic cemetery, suggested by acraven). While not unknown to tourists, especially literary fans of Shelley and Keats, it shouldn't be overrun with them. At least that was the case when we were there.
https://www.cemeteryrome.it