I'm sure this has been said before, but that's one of my bigger complaints about the Star Wars movies. They have a pretty long track record of killing off otherwise very interesting looking characters, or people who seem badass, very easily.
Everyone I knew when I saw Ep. 1 the first time was very disappointed when both Qui-Gon and Maul died...the theatre just about screamed when Jango went down against Mace...Boba was killed by a stupid accident, even though Expanded Universe fixed that...I don't think Dooku was as big of a deal, because he at least had two or three good scenes...Mace, I think, was one of the biggest let-downs of the new trilogy...they say he's this total badass...he can take anybody, all that, and then we only see him fight once, and then he gets sneak attacked by a guy who he was already very suspicious of?