Hi Jeff,
I think one of the difficulties with obtaining clips of Ueshiba, Chiba, Yamada and other top sensei clips if copyright - as most of these are for films. Aikido journal has some (but I presume they have the rights to show them 'cos they want to sell videos):
http://www.aikidojournal.com/Video/index.asp
However, I would support your idea for more clips, particularly from Shihan(and particularly older footage), if they are not copyrighted.
Ian