I don't like using the term myself or referring to Luca$. The point isn't really clever anymore. And really, does anyone still need to be convinced that Lucas hasn't totally sold out? No.

Back on topic:

It is easy to point to characters that can ruin a series, but a bit tougher to find ones that add to the series. Lando in the first post is a great example of this. Would Boba Fett be considered in this vein? Granted, he was totally thrown away in ROTJ, but as far as his appearance in Empire, he really made the franchise even cooler, for a while anyway.