Trying to plan your IO Resources on a Cortex Device is quite challenging. IMO you need a spreadsheet for that... so Check out the GitHub links.

https://github.com/s31108/STM32F4-Evaluation-Board-Free-IO-Pinouts

https://github.com/s31108/STM32F429IDISCOVERY-FreeIO-Pinout

Also see that ST offers a Tool for windows STM32F4CUBE (or it's part of CUBE, I am not sure) to interactively plan yout IO resources. My Spreadsheets are already a year old and I think CUBE was not yet available.

If you find an error, pleas write me.