This is a great guide. The only quibble I have with it is the part about choosing an instance. There’s one aspect where it does matter: not every instance federates with every other. It’s good to be aware of any significant defederation vs what you care about when selecting an instance.
I had a phone with this and I loved the hell out of it. Could tell at a glace if a notification was for an email, text, or voice call without opening the phone. Could also set a custom color for, say, a text from my wife.