[quote=@Superboy]
What exactly would you consider an independent comic book character? One that's featured heavily in its own line, or one that's written primarily [i]for[/i] comics? Would something like IDW's Transformers (properly tuned to more easily fit the setting) be acceptable? Would Dark Horse's take on Aliens, or the various different versions of G.I Joe?
[/quote]

Basically anything that isn't Marvel/DC. They don't have to have originated in comics, so I wouldn't preclude the use of something like GI Joe or Transformers...

With that being said, I'd be hesitant to give the go ahead to an Earth-set Transformers story, at least off the bat.