You get streaming replication out of the box now and you get WAL-based replication assuming you configure a shared drive or use something like S3. The latter isn't super fun to setup automation for. Also not much of a story for logical replication (tried slony, meh, feels like a relic of olden days when every deployment was carefully hand-massaged into existence) and for automated failover.

Nowadays you actually can skip a lot of setup automation with RDS, with backups, read mirrors and automated failover taken care of for you, although you frequently hear folks complain about some of those scenarios not working as nicely as you'd expect.

Improved, yes. Fixed, no. Basically if you want proper full replication, you won't get it out of the box, but will have to use various third party tools. That being said 9.4 added a bunch of the fundamental changes that that laid the foundation for full replication, now we're just waiting PG to finish exposing those features with userland tools.

Yes, it has improved a lot and is continuing to improve with new replication features every release. The built-in replication covers the simple master-salve replication case, and is simple to set up and stable.

Wondering on the same thing, anything PG working on to ease this?