I think this is a great idea, might encourage people to add more missing fanart. Are you looking for show specific ones or just general, could be used for any show templates? I'm not too precious about my work (unless you make money from it, in which case me and some friends will be forced into a somewhat magical quest to hunt you down. There'll be swords, big spiders, arrows and more than likely I'll cry. We'll all be a little richer for the experience but, was it really worth it...?) so I'd submit stuff. In fact I might have before.
Don't be modest, those are good. Nice colour choices and composition. For the Season Banner, have you stretched the text for the Season and slogan? Please don't, it makes them look disconnected from the rest of the art. Not helpful for templates but when you want to merge to layers of similar colour, merge the separate layers and then use the smudge tool at the join. Zoomed in and no one will notice the join.
WIth a bit of technique you could get a cleaner cut out of images as well, magic eraser isn't always that great.
The wide banners are particularly good, nothing but thumbs up there.
Please link to the series/episode page and your sources. Wikipedia is NOT a valid source.