I disagree with playing in the 9 AM PT slot, but think that PAC12 After Dark is just a terrible idea.
Heck, I don't know how you Eastern Time Zone folks handle "primetime" games. Games start at 8 PM ET? College football games often exceed 3 1/2 hours... So you're up until nearly midnight to watch the highest-profile game of the week?
I'd shoot for just the noon or 12:30 PT slot and the 5 PM PT slot. You have 12 teams. Nearly every one is "paired" in a geographical overlap of fandom, i.e. UW/WSU, OR/OrSU, Stan/Cal, UCLA/USC, AZ/ASU. The only one that really doesn't have a geographical overlap of fans are probably UT and Colorado.. Try to work the scheduling so that you don't schedule the teams in the same geo at the same time. So if UW is playing at noon, WSU should play at 5, or vice versa.