1. I used Shamir's secret sharing to send out a copy of my secret key to a few loved ones. The master password is in my memory only. If I forget the master password, I lose.
2. I use 1Password, and they say they make accounts read-only once you stop paying. If they did actively delete my account, my devices have a local copy. If I lose my devices and they delete my account at the same time, I lose.
3. I don't know what you're imagining, but you need the data, secret key, and master password to have this be a concern.
4. This has nothing to do with my threat model, I'm afraid. I can't imagine a world in which knowing my IP address leads to decrypting my password vault.
5. I am and this is correct. If there's a vulnerability in the cryptography used by 1Password, I lose. As you said, if there's a trojan update, I lose.
6. This is the same as 1 and 2.
All things considered, as a regular person who is concerned about protection from thieves and not especially concerned about being a target of governments, I am OK with these risks.