"Intuit aims for the most frequently used pages in QuickBooks to load within 10 seconds..."

Ten seconds? That is way too slow for a modern application. Simple text drop-down lists (eg. Customers or Vendors) cannot even keep up with an average typist like me. Those could easily be moved locally for faster response. I have worked with a number of cloud-based applications, including far more complex ERP packages, that do not have the response issues of QBO.