My son asks these type of questions at least every few months. I usually tell him that I have no idea which super power I would choose, because I really like being ordinary. Plus, everyone knows there would be too much responsibility associated with having a super power.
I can't remember all of the interesting super powers he has come up with over the years (he's 15 now), but one is having control of gravity. That would be cool, since you could use it to fly, move furniture easily, sleep on a floating bed, stop a bullet....
I guess I could trade in my sense of smell...even if it dulls my sense of taste. But then hopefully I would always have someone with me who could tell me if something was burning. Oh shoot, that would mean I could never smell patchouli again! That's not good, so maybe I should keep my smeller.
I would be willing to give up the sense of touch only if it was just the fingertips. I would hate to have no feeling anywhere in my body! You never said we couldn't negotiate our loss, so yes- loss of touch but only in the fingertips!