Though you're certainly correct about the lack of set list or arrangement variation, I may beg to differ here. Dylan in live performance from that period to me is more interesting than hearing a bunch of alternate studio takes, as their character often varied depending on mood, audience response, etc. In fact, the famous electric Manchester is relatively tame compared to gigs like Liverpool and Melbourne. Also, the acoustic performances changed in texture over the course of the tour - Dylan mostly playing it pretty straight early on, later changing his approach with more exaggerated phrasing and expansive playing, particularly the final gigs in London at the Albert Hall. Moreover, the variations in the character of the recordings themselves make them that much more intriguing. Finally, you have the wealth of chessnuts from his audience interactions - including his brilliant techniques of "crowd management".