So this actually turned out to be a good idea? Anyone want to post some more screenshots of what you've done? You can redo the textures of the monsters, the scenery, the characters, etc.
Still, I'd take a look at the license agreement or ask someone at Outspark. Although they won't be able to find people who are using the skins, posting them on a forum like this might get someone in trouble.
Yeah, I wouldn't mind downloading custom skins for Fiesta. It's a really fun game and addons would be kickass. It'll be just like WoW, but it won't suck.