One thing to remember is that franchises don't just pop out of nowhere; they're like any other idea, at one point they had to start from scratch and earn their own popularity and status. Simple name recognition cheapens the whole deal IMO; as long as you create something that captures the public imagination in a manner that they'll 'get', you stand a much better chance of coming away with a product which both you as designer and the players and buyers will be satisfied with. And you can still create something 'original' within a licensed framework; the two best examples that spring to mind being CFTBL and Monster Bash. If it weren't for the Universal Studios name attached to them, you'd swear both games - one being about 50s movie culture and the other featuring the characters in a completely uncharacteristic scenario for laughs - were dreamed up by John and George after a hard night on the piss.