wouldn't this required uke to be a great deal more skill, internal skilled, than tori since uke controlled the interaction?
I don't see how. One can apply aiki on a dumb external force, so no skill required by uke. (You do want to learn how to apply aiki on someone with internal skills as well, though.) Being thrown, joint locked would require uke to know what is being trained and tori should be able to facilitate this.
Rather it seems to be the case that tori needs to be more skilled than uke to be able to apply a joint lock in such a way that it trains uke's 'power pathways'.