Proton (free - 1GB storage, 500MB before doing 4 "tasks") for family, friends, and business types uses, although I'd rather have an integrated calendar (instead of it being a separate app).

Tutanota (free - 1GB storage) for bills, purchases, etc., basically everything else, because I'm never going to say "my email is xxxxx@TUTAmail.com" to anyone I know, especially business acquaintances. So far, I like Tutanota more than Proton, especially the integrated calendar, but that name...... sounds like something my mother or grandparents were scammed into using.

On desktop, I'm currently using Thunderbird (TB) for a couple of older gmail accounts (in the process of transitioning away from), although I hate the recent update to TB. Haven't tried the Tutanota desktop app yet, but web version of email & calendar work adequately. Maybe I'll transition from TB now, after their recent changes.

Considered mailbox.org, but I'm not going to pay for it (no free version), especially when they don't at least have a cell app. Skiff may be worth looking at. Can't recall why I didn't try them.

EDIT: I've now installed Skiff (free - 10GB) as well and liking it so far. Using webmail seems easy and straight forward, cell app looks about the same (but haven't spent too much time on it yet). REALLY like that you basically get 4 email accounts (1 main and 3 alias account names), which is different than Tutanota and Proton. With the different aliases, this gives me an option to use Skiff for everything (if I choose to "put everything in one basket" at some point). Skiff sounds a little better than "Tuta" for business acquaintances as well, but not by much. No integrated calendar, but significantly larger storage is a plus.