I never really rated Powell, but if we're looking for an experienced head that doesn't threaten the development of O'Connor and Johnson I could see this as a possibility. We'd have to go for real quality in other positions though.
Re: Johnson, I didn't see him in the Academy, what kind of player should we expect if he reaches his potential? Even more than O'Connor he seems on the small side for a forward, and I'm not sure he's ever shown a lot of pace coming out of DH either.