Overall I think this is well written. I agree with @poVoq@slrpnk.net that the section on picking an instance could be improved, since which instance one picks can be rather important, since federation/defederation is dictated by individual instances.
And a minor typo I noticed:
leaving Mastodon out to try
I assume that should be “out to dry”.
If you hadn’t specified “and other footware”, I would’ve found myself in “Eric and The Dread Gazebo” territory.