Your concerns are valid, but at least for 1 and 2, you can be proactive about preventing them, compared to preventing loss of your Google account which is just... crossing your fingers.
As for 3, well, I really don't care in the least what happens after I die. I won't be around anymore.
I can't really speak about how much of a problem 4 is, because it's never happened to me. I suspect the people who get their email classified as spam while using a large email provider actually are doing something wrong.
As a sender, you don't know when #4 happens. Regular people don't check their spam folders. Regular people don't go out of their way to give the sender a head's up that it was classified as spam.
I know it happens to me, because I have to verbally follow-up sometimes.
The only way you would know if #4 doesn't happen to you, is if you're doing something wrong, like trying to track when people open the email.
As for 3, well, I really don't care in the least what happens after I die. I won't be around anymore.
I can't really speak about how much of a problem 4 is, because it's never happened to me. I suspect the people who get their email classified as spam while using a large email provider actually are doing something wrong.