For one, levels are much shorter and there are more of them. About 1-2 minutes is the perfect amount of time for these levels to show their gimmicks and move on. Unleashed levels were bigger chunks, and there weren’t many. They long overstayed their welcome, especially the bosses taking up 15 minutes (that’s an A rank btw)
Sonic actually feels like a controllable character in this game unlike whatever he was doing in Unleashed. Hard to explain in words, but he actually turns when you move the joystick instead of being carried by 500% momentum.
The best way I can describe Unleashed is QuickTime Events: The Video Game. Colors isn’t like that (at least they’re not as common).