Hi Pete,
I'm sending you a couple of links of more possible ham operating possibilities a HEO could provide ... in addition to the nice DX we enjoyed.
A few years ago when another HEO seemed feasible I let my imagination go to work and wrote a couple of "proposals" for amateur radio missions ...
1. Use HEO for communication links in large-scale Incident Command Systems. I wrote a symposium paper for 2008 on this topic and CQ VHF Magazine also published it: http://home.comcast.net/~k9jkm/CQVHF_Eagle_ACP_Emcomm.pdf
2. Use HEO to expand ARISS School Contact time from 10 minutes to whole orbit coverage (AMSAT Symposium 2009): http://home.comcast.net/~k9jkm/Education_AMSAT_Eagle.pdf
(Note both of these were strawman proposals that haven't gone anywhere until flying high becomes a viable option again. Had AO-40 survived we could have started on these projects as well.)
Perhaps this will give an additional talking point or two in addition to the DX. Good luck with the talk!
-- 73 de JoAnne K9JKM k9jkm@amsat.org