Hello, @The Sewer Doctors.

The notes section in the Customer Information window allows you to enter 650 words or 4000 characters including spaces. I definitely understand why the ability to drag the notes section to add more information would be handy. Our developers implement features based largely on the preferences they receive from our users. I'd personally forward this to our Product Engineers for considerations in our future updates. 

In the meantime, you can consolidate your customers information in one document and attach it to your customers information.

To stay in the loop about our latest news and updates, I recommend visiting ourQuickBooks Online Blog. 

I've also included here a link which you can read through about the recent changes in QuickBooks: What’s new in QuickBooks Online

If there's anything else that you need assistance with, let me know. It'd be my pleasure to help. Thanks for coming and have a good one!