I think Proton is a good choice. I’ve heard good things about them.
For me personally, I’d be worried about putting all my eggs in one basket. For example, I like having my password manager (Bitwarden) entirely separate from everything else. I know that’s not how the general population thinks though, so I think all-in-one solutions like Proton (and also Microsoft’s and Google’s paid suites) definitely have their place.
Do Proton have a larger plan with just email and calendar?