non-centralizing defaults come with outbox to begin with. however the user discovered nostr already gives a point of entry into the ecosystem, that could be following someone or connecting to a relay. and for obvious reasons, your third option is objectively the best, users need to have a basic idea of what goes on behind the UI so that they can make conscious choices. i agree with you that it gets really confusing, and thus the reason why this space needs more UX designers which are good at dealing with decentralized tools.