While I agree with a lot of what you said, I think we did see considerable emotional range in Sleeping Beauty--Jason really shone in that ep, where he had more to work with as Josef. But I've always thought that Josef, as a character, was very nuanced. He's in control, but there always seem to be layers of meaning, and emotion, under almost every move he makes, and every word he utters. (Not that I've given this much thought, or anything...

It's true, we didn't see nearly enough of Josef to give Jason the scope he could have brought to the character, but damn, he sure did a lot with what he had.
The very cool thing about Logan Echolls is the development of the character--again, it's a nuanced take, because all that angst and need for love is always present with Logan, it's just that at first, we as viewers can't see it, because it's rolled out slowly, over time.