An actitude wich is used in Japan in this aspect is: "If you don't like it, ignore it"
If the characters belong totally to the creator, ALTERNATIVE CREATIONS would be forbidden. No matter those are fan fics or fan arts or hentai or nothing of that.
The doujin world is not possible to control. And no all the artists are those perverted hentai artists.
For me, no reason to control that because the conception of "good" and "bad" changes with the person who see that. I like hentai (I am repeating me
) and you detest it. Who is the more suitable to judge this "problem"? Neither me neither you. Neither anyone.If you only want to see the "proper" works, it's ok (I like those too ^O^) but that's no a reason to ban the other works, wich are so respectable like the first ones. If you don't like it, ignore it (no matter how famous turns it: Never will be official ^_^).
That's my opinion.
P.D.: I like a enormous videogames saga. Her name is "ToHo" ("Eastern"). Zun, the first author of that saga, does the games. And the fans, almost all the rest (comics, flashes, arranges of the music, fan fictions, hentai doujins (: P) and, even anime (something is done... and in the next Comiket, in August will there be an "serious" anime...)). The fans, proper or not, are growing that saga with their amateur works. Maybe, those not are official, but still being a good work. Because of this, my opinion is that I has expresed before. Not only because I like the hentai.
P.D. 2: Argue more! So this forum could recover a bit of life ^O^
P.D. 3: Oh, and sorry for my nasty and stinky english : P