It kinda reads like their user's data is not separated very cleanly; I've never worked at a SaaS before, but reading this, especially given the size of some customers, I'd want each customer to have their own independent instance, with its own backup pipeline. I was thinking of "just" giving them their own database, but there's been plenty of instances where authentication got botched allowing one user to see another user's data; this should be impossible if things are running on their own instances.

Note that I'm pretty naïve and armchair on this subject, I'll see myself out.