Over the years, I’ve been studying a handful of different fediverse platforms that bring a lot of interesting concepts to the table.
As someone that has studied and reported on the developments of these various systems, I’ve decided to put together a summary of things I’d like to one day put into my own federated platform, should I ever develop enough brainpower to actually develop one.
Lots of the things you mention are as you are probably aware already in Hubzilla. But I think it is safe to assume that those will not see much uptake in the wider AP ecosystem.
As for federated accounts, I think the most feasible is probably some sort of out of band login option similar to how those login with google (OIDC) exists. However OIDC specifically does not work without such centralization.
I think Matrix is working on something less centralized like that and XMPP had a solution for that since many years that allows you to log into a website password less with a confirmation message via your IM client.