So there was nothing for it but to stump up the $270 for a flight on United that arrives in KC at 12:32, so I will arrive mid-afternoon at the hotel. The bad part is that it leaves SFO at 6 AM, which will be annoying and require driving to the airport, as there is no way to get there on public transit early enough. (The earliest BART departure from Fremont is 4:02 AM, arriving SFO 5:31 AM. While perhaps the earliest flights don't really need two hours advance arrival, 30 minutes won't cut it.)
There is no way to book a hotel room at the SMOFCon hotel through the internet, so I had to call to get the convention rate. Not that big a deal, but I prefer to book on-line whenever possible.