To clarify things further, I want to assure everyone that there is nothing wrong if a design has flaws with in it. Having imperfections within a character's appearance helps making them not be someone who is perfect, in a sense (i.e.: zits, bad hair, wrinkles, imperfect teeth, etc). In fact, it also helps making them more interesting, but
only when it's done intentionally, rather than just composing it badly and thinking it looks good.
Keep in mind, that you can't just make a bad hairstyle and then just go like "That makes him look unique!", because it would still feel out of context. Why? In comparison to how official Sonic designs are composed, your character's hair would certainly not be seen as something normal or something that anyone else can be casual about.
If it was intentionally bad, then it works better when there's some context to it, but if it's not what you intended, then you just need to do something to fix the design. It'd feel better if there was a context for the hair being so bad. To show what I mean, look at Josuke from JJBA:
Just look at that pompadour hairstyle of his. It's nearly impossible to ignore it, right? In fact, it's arguably bad, and it's certainly not ignored by most of the characters within the story, and he also reacts rather strongly to anyone who makes fun of it. In fact, there's even a backstory for why he chose to keep his hair like that-- and of course, his hair is just one small part of all of his traits and personality. If there wasn't a context for his hair, then it'd feel weird for everyone to just be so casual about his hair being so big. Your character, on the other hand, feels more like something like this:
An absurdly bad hair that is simply seen as part of his appearance and nothing else. It's overly exaggerated without any need to even keep it that far out. There is nothing wrong with big hair, but the one you made is just so out there while not really looking any interesting from front and side angles. For a hair that big, it would work better if there was some more variation on his hair's shape, rather than just leaving a gigantic triangle on the back of his head. I personally think it looked way more interesting in the previous design.
TL;DR: Either shrink the hair or make it not seem so flat. Preferably shrink the hair.