One Hit Noob said:
There is a thread called "The artist in thee", you should check it out.
I'd second that, and, to be honest, I'd like to see it stickied if a dedicated subforum isn't feasible. Ok, so the facility is not necessarily part of the site's remit, but neither is giving general advice, which has its own subforum.
For those claiming there isn't any demand for such a facility, I think it's more than the current setup of the site is unfavourable towards sharing user created works to the point that most would simply not bother. As others have said, there isn't necessarily much in the way of discussion value provided, so it's likely that in Off-Topic, the only subforum which really accommodates most things of this nature, any thread with user submitted content is more likely to quickly vanish off the front page. There's no visible demand, I think, as the nature of the outlets allowed to forum users discourages any attempts.
I certainly think that enough forum users engage in the kind of pursuits that would make a subforum of some kind for this purpose worthwhile, and a presumably slower pace would make valuable feedback more likely supposing people who produce similar stuff take an interest in seeing what others have done. I'd expect it eventually develop more of a coherent community than the Advice Forum appears to have. I've wanted something along these lines for a while, especially since the recent User Review rules seem to shutdown any analyses, which, to be, would seem ill suited to Games Discussion too. Posting my thoughts here won't do much good, but hey, those are my thoughts.