I imagine for a Sonic game that Sonic runs so fast time slows down fo Sonic which it has a visual representation for it due to how the environment is. Seeing birds fly slower as you speed and then they seem "frozen in air", waterfall falls slower, IDK even leaves falling slower and all can contributes to this feeling.
And then Sonic may actually "curve reality" as in he runs so fast buildings being bended so thus he can run on their surface without jumping or any interruption, even whole city can be curved like the movie Inception so you go fast around fucked up state of time-space bended city. However it calls for a way to adjust Sonic's speed to intentionally curve the world in the way you want so the curve will depend on how fast you are so you can keep running without slowing down so it can make a sense of "envoirement puzzle" Sonic games tend to use but they mostly use it via dead ends and platforming which is a drag.
Also Sonic can even run so fast he goes back in time so running around the city you see how the city was going backwards in time, so buildings eventually get into their "during construction state" and then no buildings around, just villages and shit. It can be part of a puzzle to running in a particular speed and duration to go back to particular time frame to do some stuff IDK. Also it can be a way to open yourself a way to progress to your destination. And then just for "video game logic", the time will eventually get back to the current time if Sonic doesn't run that fast so Sonic can have 3 speed states. In 1st state he just runs, in the 2nd state he bends the environment, in the 3rd state he bends space-time so thus he goes back in time.
The potential of Sonic IMO was ruined in new games with slower gameplay and more platforming. Sonic can be so fast he shouldn't be limited with running on the ground. There can be more running on the ocean and even "flying in air by running" stuff. It was always cool when he could run on ceiling to emphasize his rebel personality by even defying laws of physics so we can even go deep into quantum yo lol. Despite they wanna do something "different" the difference they can still be limited to ancient video game design and a difference that make the game away from being a Sonic game without any sense of improvement whatsoever.
In the end these ideas are fundamentally used in Sonic games, yet what I mean is improving these ideas for the non-scripted but dynamic aspect of the gameplay. But my idea heavily focuses on visual representations of it for visual masturbation and these ideas IMO enables a fun Sonic gameplay in the context of how Sonic was. IMO Sonic doesn't have to be too different, it can do what it did before better.
