Hi Eliot_Cole , thank you for your comment.
Sorry you've had trouble finding our documentation, I've linked it here so you don't have to dig: Section Design Ideas - Microsoft Support. You can also access this documentation by clicking "learn about design ideas", when you have a configuration that we can't generate an idea for.
I hear you on stuff like this being annoying- I tend to be more of a DIY person myself when it comes to page design. The good news is we made sure this was unobtrusive- it doesn't automatically open up but is there if you want it. On the AI side- if it helps, this feature is actually pretty light on AI, we haven't added any new capabilities to the SharePoint canvas, just used the text summarization service to find keywords that we can use to pull relevant stock images. That being said, for tenants that for security reasons have all AI whatsoever turned off, we will suggest general abstract images so users can still easily add different designs.
You don't by any means sound overly negative, your concerns are important, and I appreciate you helping us get this right 🙂