You could delete some uploads, and i think that will allow you to re upload some things, anyway take in mind that as an scouted artist all your non sketch submissions will appear in the art portal so there is a limit, try to make 1 or 2 uploads per day and 5 per week, something like that.
Doomroar
Well that is mostly to prevent spam so it can't be helped.
AndreuMB
Yeah, I supposed so. Anyway it sucks to me. I think it was enough with the daily limit.