Got to be honest here this isn’t exactly jawdropping or badass it’s just coasting towards bad. Now before you complain at me for being rude and that’s fair. Let me help you out here. Apply / do this:
-Don’t use a scarf unless it’s done well and not just a few rounded segments put together -give it edges like how a scarf would have (not to strongly though)
-Change the colours you use to a fainter set.
-Come up with a more unique OC, add detailing and a cool story if you want. Don’t just go by he has powers, he is strong and looks cool because that’s just plain bad. You need to elaborate your idea more.
-decrease the strengths of the filters because it makes the image look weird up-close. Instead use blur and opacity change to your advantage, layer colours on top of each other with blur and decreased colour shade / opacity so it looks like glow.
-Add shadows / lighting (not just gradient ellipses, that’s just lazy, decide a set point where light would be coming from and do shadow highlights on the opposite side.

This may all seem a bit much but considering this is one piece of art I say you should go all out and make it look amazing so instead of getting accused of using scarfs on a stickfigure etc. people will praise your work.