You could also look into using a fully open source Android, such as lineageos (forked from cyanogenmod). Just don’t load any Google apps packages when you install and you’ll have basically what you’re looking for. (That’s what I’m using, and I use the f-droid.org repo to add a few other open-source apps).
Edit: Also I know what you mean about unplugging. Personally I don’t want to totally unplug per se, but I also don’t like my phone interrupting my day unless someone is actually calling me so I do keep my notifications silent, and as I mentioned I only use a handful of simple utility apps (no social networks, chat apps, video apps, etc). It’s helped me find a balance between keeping my sanity and not being a total hermit.