I mostly agree with your rules, they seem well thought out. I have two objections: Firstly altered versions of AP seems hard to enforce. I think if the versions of AP are compatible enough for federation to work, we should let it run.

Secondly, and more importantly, the part were you want to defederate with servers that do not follow these rules is a really bad idea. If some small instance wants to consume the content from threads, their users may still add content to the fediverse. I think these rules would be a good recommendation for any new server admins and committing to these rules would be a good reason to join a server. But I don’t see any reason to turn this into a “you’re either with us or against us”-type conflict.