Use a custom domain for your important accounts. That way, if you decide you don't like Proton, you can move to Tuta or a different provider and recreate your addresses there. That way, the only thing you have to change is some DNS records.
I'm currently testing the paid version of tuta and proton.
Regarding the other services, as other said, keep things separate. Personally I use self hosted bitwarden for passwords and Synology drive for well, drive.
Dick Dastardly