As a non-American, I don't trust the American Government not to compel Google to provide them access to my data.

As an American, I also don't trust the American Government to not compel Google to provide them access to my data. Yes, I know I am supposedly protected by due process- but Barr is making it explicitly clear that the 4th amendment does not apply to our digital lives.

Barr? The last 3 administrations.

And if you put it in, say, Protonmail, they can just hack it, so you're not necessarily gaining security.

I was paying for G Suite earlier this year with my custom domain and was very happy with it (especially cloud search), except: I have been using GMail since almost 3 years before it became public and there was no way to merge my old persona with the new G Suite account. I had to switch my Google identities back and forth. I decided that this was too much of a hassle.

Do you use Chrome? You can do all your personal stuff in one Chrome profile, and all your G Suite stuff in another. You can even use both profiles simultaneously (though in separate windows).

https://support.google.com/chrome/answer/2364824?hl=en

You may also want to consider only using your G Suite account for G Suite features. Certain features designed for personal Google accounts don't work properly for G Suite accounts (like Youtube/Google Play Music family plans).

https://support.google.com/youtube/answer/7507349

Unfortunately Gsuite offer is smaller than regular gmail (remindrrs, google home and posdibly others)

They punish their paying customers.