Dr. Menke? I saw your twitter. Are you a PHD? Anyway, always enjoy reading your update. Some thoughts...
Is intermission too long or too short?
My preference is to have it as is. A question for you. At what point do most players back out? Of course I do not have access to the data you have, but I suspect much of the skipping occurs as soon as the new map is displayed. If this is the case, the skip button will become a defacto map voting button. A possible solution to this is to have a toggle, much like assassinations, where you can turn off the intermission as a general setting.
What are you going to do about Champion players partying with low CSR accounts to rank up faster?
What happens when lower ranked players like myself party with onyx and champs? From experience it seems to be pretty well balanced, with the opposing team having an onyx player and golds.