Okay, so now I've tried Tutanota and Proton for an alternative to Gmail.

I like neither.

Tutanota was not great. I've talked about that in an upcoming blog post. 

Proton has given me nothing but trouble with DNS. I can't receive mail from any outside account and have no clue what's going on. The DNS says that everything has cleared, but still no incoming direct mail. Maybe doing something wrong, but I don't know what it would be.