If I had 3-4 services and a bunch of databases, I would look at them and ask "why do we need to introduce network calls into our architecture?" and "how come we're using MySQL and Postgres and MongoDB and a Cassandra cluster for a system that gets 200 requests a minute and is maintained by 9 engineers?"

Don't get me wrong, maybe they're good choices, but absent any other facts I'd start asking questions about what makes each service necessary.