I've got a minimal marlin build up and running on both X and K, with the boards wired into a printer to test with. Doing so has revealed a few problems I would not have seen otherwise:
1. My LCD isn't filling the background correctly. The Logo during boot appears clipped, and the boarders are not filled in black.
2. Hotend temperatures read from PC1 are not working correctly. i can swap the pin definition to PC0, swap the connector, and the hotend behaves correct. This doesn't affect the MP MIni, so it's not clear to me what might be happening.
The solution for #2 is to write some diagnostic code to narrow down if pure, plain "analog read" works for the pins. Once basic pins are verified, I'll begin PRs to add this to Marlin main.