Lot of symbolism in his look. The roboticized arm was a warning by Robotnik. Angelic blues (that compliment Sleet’s devilish reds), & after his harrowing experiences & stripped from his aristocratic life, he adapts better than you’d think. Stable & enlightened from such change. The opposite of Dingo in every way. It is his newfound valiant and empathetic heart that steers Sleet to the light… and back to Dingo.