I think the word posed can be omitted.
Also, I think this part will be better with a small change, like this: One of the major concerns against freeing artists' creation is derived from the fear of ...
artists always discover a way to express themselves.
Good point, Cornelius! I agree with your idea...
Xin, you forgot one apostrophe: be put on artists' work; on the contrary, they should be encouraged to express their innovative ideas. This world needs them to make itself colourful. -----Also, I think the ending will be more poignant as a separate, short sentence as I made it above.
Anyway, this essay is some impressive writing! To perfect your skill, read Strunk and White's Elements of Style. Great, great job.