After thinking it over a little, I think it might be simpler to have only hdmi ports on the conference table pop ups and provide the following adapters:
1. VGA and l/r audio to hdmi converter 2. Display Port to hdmi converter 3. DVI and l/r audio to hdmi converter
that should cover 98% of needs.
Atlona makes an auto sense 3x1 hdmi switch I could install under the table that would switch whichever hdmi port is being used on to the matrix. Another installer told me that that he has used that Atlona auto sense switch dozens of times and they work well.
Chasing Ernie's post count, one useless post at a time.