Write Ahead Logs would have been amazing - hate that AWS RDS does not support WAL - could have saved so much time for some of the applications we build.
WDYM by "RDS does not support WAL"? I wouldn't know how Postgres works without them, and they are accessible using logical decoding. wal2json is supported on RDS and used by tools such as Debezium for streaming data changes into Apache Kafka (Disclaimer: I work on Debezium).