The best solution would be that every user only downloads the images he really needs. So... if we ignore TheTVDB.com for a moment a solution would be a dedicated website where user can select the images they need from a list (with thumbs) and only download these. In addition there could be an upload function.
A dedicated website sounds like the best thing to me. Did I miss something: Why can't we use thetvdb? I mean, at the end of the day this could be handled similar to the series banners (even if there will be different fan art files for different languages). And the general download code should be available in the MP-TVSeries plug-in.
PS: This would have the advantage that the data wouldn't be wiped with a database cleanup.
G.B.Wolf: I am not sure what you mean with this.
Germany