It's in the question. Should I go for speed or power? Here's my set:
Pidgeot @ Pidgeotite
Ability: Big Pecks -> No Guard
252 SpA / 252 Spe / 4 HP
When a Pokemon has a high speed tier they can put to use you have to have the nature for speed or else they can't use speed to their advantage. It's common knowledge in the competitive world
If one of those 2 Timid. It needs speed more then special attack.
I would go with hasty (+speed - def) tho so you dont lose power on u-turn.