Feedback round two!

I like your design of the circuit, well done!

A few comments:

• You might be missing a capacitor between 3.3V and the MCU.
• Add testing points for ground so you can measure over components during the debugging process.
• Adding testing points for the mouse buttons might make the debugging easier down the line.
• Depending on which encoder you've chosen to use, you might have to make a custom footprint.