Kreia- Awesome. Weird to think she does commercials. "Betrayal...." also her dialouge when you go in to see the Jedi Masters went well with the BG Music.
"Know that much will happen. You may trust me..." probably manipulative but it sounded convincing.
HK-47- Whoever does it- your the best! Unknownly evil, which makes him quite amusing. Without the voice, HK would be Jar Jar Binks.
I really don't have a third favorite.