I would choose super strength, it would come in handy a lot.
Shapeshifting
Well .. That would depend on what i am trying to accomplish .. Sometimes .. When I am at my wits end, been struggling and have exhausted every option and can't get that one stubborn stain out of my hubby's favorite shirt .. I would like to have a supernatural powder.
Oh wait .. You said 'power' .. Sorry .. In that case .. I would just like to fly.
I will ask for one more supernatural power.