Game Developer is a Programmer.
Content Creator is an Artist.
Do you mean Content Creator?
If you do mean Content Creator then I highly recommend you join an indie team or modding community. This way you will receive feedback that is useful for the positive outcome of the project/game.
I have seen you post a few times in the past, here and on CGSociety and have not received many comments. The comments you have received you have ignored. I highly recommend you take on @JordanNVFX feedback from CGSociety, this person have given you good advice - which to summarize the comments for other readers was: focus on a particular discipline - character, prop, environment etc before becoming a generalist.
One last note is that presentation is particularly important in artwork. Check some references of artwork you like, try to replicate that style/lighting/composition. Not only will your artwork benefit from a professional layout, it will help you see where your flaws are since its easy to compare apples with apples.
