'bout a year late here, but whatever LOL
The best part about this mod is definitely the character's design. It feels distinctly "sonicy", while also totally being it's own thing with a completely unique feel to him. I get a much more... relaxed vibe from him then you do with the typical sonic crew. His sprites, while a little unpolished in some areas, are also far from terrible, though the offsets can be a little janky, and I 𝘵𝘩𝘪𝘯𝘬 you may not have do a2/a4 roll frames(?), though that's fairly understandable as roll is one of the hardest animations to sprite.
In terms of his moveset, this is where I have the most issues. It's not that I dislike the concept, far from it, he just feels very... underpowered. The twirl is quite difficult to time properly, and even if you manage to get it down perfectly, I still don't think it's powerful enough to warrant needing to learn the timing of when you need to hit spin again if you don't want your input to be dropped. Personally, i'd simply allow you to hold down spin to keep automatically twirling instead of needing to time it perfectly to maintain the most possible height. The twirl thok also doesn't really feel like it particularly compliments the twirl if i'm being honest, a character that appears to be very verticality focused having a move that simply propels him forward seems a little counter-intuitive to me. Personally, i'd go with something more along the lines of yoshi's flutter jump if I was to design a new kit for him, it'd definitely help accentuate the whole "floaty" vibe you was going for with him. Being able to get up decently high with a combination of his naturally high jump & a verticality focused doublejump ability would help make his whole playstyle feel a lot more cohesive imo.
Overall, this is really good for your first mod!! It's got it's issues, but it's clear you put a lot of love into this little guy. Can't wait to see what you create in the future!
I have some questions but i'll come to you directly about that :p