Hmm.
I'll have Platinum sooner than I thought; we got an unexpected child support payment. I'm going to raise a Butterfree. I checked out the Platinum tutor moves that ButterFree can learn, and it gains Air Slash, Ominous Wind, and Twister. Other good attack moves it can learn are Psychic, Bug Buzz, and Energy Ball, though I'm not sure what it'll have.