Hi @pschall42, welcome to the forum! 
I'm sorry you are experiencing all of these issues. It can be frustrating to put so much work into building an application only to encounter bugs like these. There's a lot to touch on from all the issues you've surfaced but before we approach them individually, I'll share with you what I've seen in the past.
A few weeks ago, a customer came to Office Hours reporting similar issues, queries running on page load despite the fact they were set to run manually, queries taking too long to run on page load, the editor slowing down significantly, etc. When we took a closer look at their app, it was a massive app that had a Tabbed Container, where each tab was basically a whole app on its own.
Performance of Retool apps is primarily impacted by the number of code blocks and components. Essentially, every app is a JSON object with many dependencies, the bigger the app, the more (deeply) nested dependencies it needs to update with new changes.
Please share a screenshot of the Performance tab in the Debug console. You can open the console by clicking 'Debug' at the bottom right of the screen:
