I definitely agree that certain moves should be Sketchable without a medium, but it's going to be hard to establish unanimity as to which moves would/would not require that medium. I mentioned this to DL and I think we're already starting to see it. Everyone would probably agree that Protect and Magic Coat, for example, shouldn't require a medium. With Aromatherapy, it's a little trickier. Personally, I think Aromatherapy should require a medium (ie. an incense burner, jar of potpourri, etc.), but I also sort of understand why you think it shouldn't.

I disagree that this nerf to Sketch renders Smeargle "little better" than a Pokemon with only Mimic/Me First, though. Smeargle still has every move in its arsenal, but those moves just can't be called upon directly. Unpredictability is absolutely still on Smeargle's side—more so, I'd say, than any other Pokemon. (You're also right to suggest that Smeargle is pretty useless if it's Taunted, but hey, so is a non-Imposter Ditto.)