(i) Starmie won't make use of the At. advantage from Swords Dance,
(ii) Starmie is already so fast that it doesn't really need the Spe. advantage, and
(iii) Life Orb generally increases the utility of damage-dealing moves (viz., Thunderbolt) over stat.-altering moves.
Then again, Starmie's versatility means it can put defensive and evasive state boosts to good use.