Migrating to Postgres will certainly be significantly more work than going to MariaDB for you. But I would still recommend you consider it, because Postgres is

Migrating to Postgres will certainly be significantly more work than going to MariaDB for you. But I would still recommend you consider it, because Postgres is safer, more powerful and has fewer edge-case behaviors. If your systems are highly-wedded to MySQL's idiosyncrasies, the difference in cost may be too high for you to do it right now, but I would seriously consider it.