I would specifically advise against developing a tech related hobby. In my experience, it just accelerates burn out. Something that forces you to be outside/unplugged is ideal imo.
Picking up an arduino and 'waste' a couple of days making LED blink can be fantastically relaxing too.
I just think it's inevitable to hit burnout if you spend all day at work staring at screens and come home to relax by staring at screens. Or at least a way to burn out your eyes.