I think you shouldn't listen to anyone that can't even do proper drawings.
Secondly, there's millions of people with the same hairstyle. Even those edgy alternative style tumblr artists have basically share the same wardrobe/hairstyles. Like their characters all went to the same barber shop in Brooklyn or subscribe to the same mainstream alt fashion tips tumblr, thinking how cool and different and cool they are.
So i don't have problems with your hairstyle.
I think overall the character design is okay. Just the gloves may seem a bit off-putting. Also you need to spot your blacks more consistently it's just the style makes it more apparent when you don't do that. I too have problem with black spotting myself.
As for the proportion I think youre not drawing to 1:1 scale for each character so I don't think there's any problem there.
As for how good the comic will be, that'll depends on your execution.