I don't need payments to work, I've never used Gmail, and most of my apps are FOSS ones off FDroid. But banking apps must work, and so do push notifications. The latter are my biggest issue: afaik, they run through GCM (part of Play Services), and you won't get any unless an app has implemented an alternative listener (Signal does), which comes with more battery power draw. (How) do push notifications work for you without microG and Play Services?