Great advice all around @jtenter! We’ve also kept both separate databases and custom named tables for our own purposes in our SQL DB without issue. I think if we had to do it all over again, we would have started with the custom database ONLY approach as it does make it much less likely that an upgrade could wipe out your custom data.
The only consideration I’ll add is that you might consider offloading some of this data to a business intelligence product like Azure Data Lake, PowerBI or Tableau. Some of those reporting specific platforms can provide more flexibility in terms of reporting tools for stakeholders rather than relying on a relational database structure.