Due to the pinout/footprint of the SK6805 RGB LEDs, it was more beneficial to arrange them so that the final ghost was LED 0, and Pac-Man was LED 4. This way I was able to connect DOUT to the next LED's DIN with a direct line.

This ended up being a tradeoff between software gymnastics to mirror the indexes, or having a far more difficult to route PCB layout, particularly with all of that empty space where I can't have copper or soldermask because I want only the FR4 exposed to allow the light through from the back.

Just remembering to mirror the indexes proved pretty straightforward and in some case you can use easier helpers e.g.

#define PAC_MAN_LED_INDEX 4