Finished the game up in almost one go, since I've gotten a game over in Ice Cap 2. I'm glad this project was completed, as in terms of quality it's a pack of stages that feels like a DLC for Sonic GT, which is a good thing. My personal problems I've mentioned were not addressed (except for 2 bosses being unfinished which was a must to complete) but I still think this fan-game is very addictive in terms of it's level design and just the overall flow of gameplay. We've never seen Oil Ocean, Mystic Cave and more in 3D, so it was interesting to see someone's interpretation of them. I still had the problem with Ice Cap 2, as I mentioned earlier but it's no longer my complaint, as I see you are basically done with this. Bosses were hit-or-miss, because they were either too easy, or too annoying. The first two bosses were the only consistent ones, in my opinion.
By the way, if you do think about polishing further, I'll just say that DS4 compatibility is busted, forcing me to add this game on Steam and emulate XInput; and Knuckles, while it's great that he can climb, it actually makes him broken for the level design as he can glide and climb through basically every obstacle. I'm pretty satisfied with how this turned out and I'm hopeful that you will have more projects planned in the future.
the Chasing badniks I'm still trying to find middle ground as last year feedback was mixed, some liked them as they are which were more aggressive and has a bigger distance before they reset. this time i scaled them back. perhaps not enough