That'd be an interesting plot twist. A group of ghosts in the ECU who oppose Tempus and assist the GB's in stopping him. Im thinking Sherlock Holmes and Watson, Syren, Drool, The sleeping ghost (more of a berzerker really he just dosent want his quiet sleeping place ruined) and here's a curve ball...Samhain who's doing it out of spite as he feels he should be leading the ghosts and demons.
I must say I wish the Tobin's Spirit Guide thing had happened, too! I was really looking forward to it and seeing this brings those feelings back. I love your version of Tempus here; very dark and corpse-like. I always enjoy your grittier interpretations of the cartoon villains.
If they did it right--making it a really solid and thorough version of Tobin's Spirit Guide--people would eat it up. I imagine it would sell better than the comics because then they could snag the people who are in it for the art or for the cosplay/prop uses. If you're doing the art we know that aspect of it will generate good sales; I think what may make/break it for the cosplay/prop community is if it could pass as an old book; with cloth cover no text all over the front or back, and just that "T" symbol from RGB's depiction of it on the cover.
Just my personal feelings on what the community is looking for.