In our cloud offering logical replication is not yet supported. There's an open epic to support receiving a logical replication stream [0], but we've not yet checked on sending logical or physical replication streams.
Everything you've described sounds unbelievably awesome - this is the only thing I can think of that would make it better. If we can get all of these features (I've been dreaming of branching for years, scale to zero!, unlimited storage - just not having to think ahead about it!) plus easy, even on by default logical replication, you will have found the holy grail of cloud databases imo.
