The option to customize the zoom intervals beyond the preset 25% increments isn’t currently available, windyl0u.
QuickBooks Desktop is designed to function in alignment with your computer’s screen resolution and display settings. As a workaround, you can adjust your system's display scaling to 90%. 
However, the effectiveness of this scaling option depends on your monitor, as most monitors are optimized for a default scaling of 100%.
Should you have further questions, let us know in the comments.