I'm in the market for this, albeit for different reasons. Perhaps coincidentally, right after Google announced ending their free storage their sync started acting up for me. Even though I'm a _paying_ customer. In that circumstance the usual Google lack of support becomes quite unacceptable. For me the key feature is partner sharing. My wife and I take lots of baby photos. We see each other's photos as if we took the…
All of this is just using the base syncthing and doesn't require any technical skills. Backing up in the cloud needs more time and expertise, but after having done it myself and realizing I don't actually need it (a simple backup is enough, I don't need a web interface to do what I can do faster and more easily from a desktop app) and I can have encrypted backups instead. Bonus: if you're both on the same wifi the sharing is quasi-instantaneous and doesn't waste energy sending to a faraway server first