wait and see.

basically i see suigetsu as a antagonist for kisame and to help bring about a story for kisame background.

as for the bimbo and juugo they will server there purpose eventually, in all honesty karin served her purpose in keeping them away from naruto and co, and help trackin down itachii somewhat.

juugo will serve his purpose when it comes down to ultimatly later on when sasuke chooses his side.