After reading through this thread, I was thinking something similar to what you are proposing is the cleanest way forward (except I was thinking numbers instead

After reading through this thread, I was thinking something similar to what you are proposing is the cleanest way forward (except I was thinking numbers instead of letters). You could even get more clever and use colors, where complementary colors work together. Couple that with some error messages that mirror what you wrote in the last part of your post in software whenever you plugged in a USB-C device to a connector and I think the standard could be salvaged and even a relative pleasure to use given the background.