RDS is expensive, but for a small team of 5 devs (my current setup) it is an amazing solution. Scaling up and down the database is as simple clicking a button

RDS is expensive, but for a small team of 5 devs (my current setup) it is an amazing solution. Scaling up and down the database is as simple clicking a button on the UI, which we used quite effectively when our services saw a sudden spike in the load. We were able to scale down the same way after the spike dropped. We still had to tune our queries and indices so that we weren't paying the cost over the long term, but the peace of mind that comes with not having to figure out why your database went down when there is no one in the office is a huge win-win. We currently also manage an OLD version of Cassandra and Elasticsearch and we are also looking to migrate to the new managed version of Cassandra. At the end of the day, the extra cost for RDS even for small teams, is much lower than the cost in terms of developer-hours * cost per hour for developer.