I know there's nothing you can do about amature work, but atleast encrease the number of mods to help stop theft. as you said "it's too large a job for a small group of staff members. "
Most just take screenshots and edited them to their character and as for the miss sorting it makes the site look messy and displeasing. Listen so many great artist have left do to all the lying, theft ...
There's so many art theft form different sites and people putting art that don't belong in that catagory. Take the Naruto fan character fourm one girl named skygirl keeps placing random comics there. ...