I just checked your comment history and it appears that you like to troll.
How can I know that this isn't one of those cases? I know some folks in fintech and while obviously they're not _you_, they're definitely not the sort to be wishy washy with data, if anything they're quite conservative when it comes to how the databases are managed.
Any incidental complexity is incredibly discouraged.
If we need to increase storage this can be achieved in minutes, if we need to take one node down we basically can do it anytime during the day..
Every now and then we discuss moving DBs to AWS RDS (or equivalent) however for our transaction volume RDS costs are prohibitive.