I write this because I see a lot of this on Deviantart, and a few other places, and have been guilty of it myself way back when, so thought it might be good advice. I use Games Workshop as an example because thats what I have experience in, but it's equally applicable to super-heroes, manga, anime, all the popular genres.
I loved drawing since when I was small, so when I came across Games Workshop, obviously I finally found a thing to draw that suited me and what I liked. There was no internet back when I was a kid, at least not freely available internet, so all my influences came from the codex's GW used to bring out. So I basically began to copy John Blanche, Adrian Smith, Mark Gibbons, all those fantasy artists. Harmless enough, it was essential drawing practice at the very least, and schools were never really supportive of that kind of art anyway, it was always paper-mache masks.
I wanted to be an artist for Games Workshop, because thats what I liked. I used to draw that stuff all the time, I never really deviated from it, just carried on emulating what I saw. I drew guns that was based on GW, armour that was based on Space Marines, aliens based on Tyranids etc. I even wrote stories that were loose copies of what fiction I had read. I became good at drawing because of it, but I lacked any identity. I was just emulating.
It took me to my last year of uni, when a tutor said rather cryptically, that as good as drawing as I was, I lacked understanding. Later I realised he meant understanding the why of it, where it came from. And thats what emulation is, a short cut. Re-drawing the conclusion of someone else's train of thought, their research, their visual development.
So I went away from what I knew, and concentrated on me. I asked myself whats my strongest point, which was my actual physical drawing (as opposed to collage, painting etc) and then I tried to apply that drawing with something I never used to use, which was colour. Thats when I began using photoshop to colour my images, because I suck at painting, and also I found a technique that allows me to draw first and think about colour later.
Then I looked at armour, weapons, myths, legends, machinery, anatomy, skeletons, animals. All those things that I had been emulating, but not understanding. I started coming up with my own designs, interpretations and stories to illustrate. I started to become what I am today.
Emulating other artists while your growing up is fine, and is pretty hard not to do unless your literally blind and deaf, and also all these artists that influenced me gave me the courage to do what I do, and not listen to all the nay-sayers and people saying it wasn't a proper job. But at some point you have to stop copying and start creating.
I came back to drawing Games Workshop stuff a few years ago, with my Primarch series. But it's undoubtably my interpretation of that universe, not a clone. One day, maybe I will work for Games Workshop like my younger self wanted, but because I am good at illustration, and have something new to bring to the table, not because I'm only good at drawing Space Marines.
I want to see Ashley Wood, or Mike Magnolia, or Killian Eng, or Chris Foss do a Games Workshop inspired piece, because they have a strong individual style that can breath life into anything in that universe. I would of loved to have read an Iain M Banks or a Frank Miller, or a Neil Gaiman's story set in the 40k universe for instance. What I don't want to look at or read, is work from someone who hasn't developed themselves as an artist, who hasn't gone through all the high's and low's of defining ones style and come out the other side.
So that's my advice, it's not easy, but go out and find yourself. It may take years, but the end result is always worth it.