I wish there was more Heel Mad Dog Vachon from the 50's - 70's against quality face opponents, like AWA title matches against Verne and Crusher, for example. Heel Vachon/Raschke from the Montreal area would also be sweet.
There is a lot of Bockwinkel available but obviously I wish there was more, especially more of his and Heenan's 70's interviews.
Stevens is another obvious choice for me, if only because he gets such significant praise from his peers in every situation and his footage is lacking.
Verne defenses against Watts, Crusher, Vachon, Hennig, Race, and so many others as well.