I will always be more free on Sundays than Saturdays, so I voted Sunday.
As for Christmas, I don't know how big of an issue it will be. I'd guess the 12/13 is safer and then do two in January, maybe first weekend and 3rd weekend then go back to 3rd weekend in Feb.
I'm almost definitely not able to make any of those days except maybe the 20th so go with majority.
turnout rates may be lower because people will think missing 1 isn't too bad because another is coming up soon
I am still failing to see this logic. I am sure many more people are with this idea of thinking: "If I can make it I'm participating, if I can't I can't." It doesn't matter if these were once every 6 months...if I'm busy I am missing it period. If I can make it 4 months in a row then I can. If it's bi-weekly I'm never going to think, "well I could make it but there's another one in 2 weeks sooo..."
The good point, in my opinion, is the ideas running dry, because I do see it being a problem to keep coming up with good, quality ideas. These first two were extremely high quality ideas. The reason? Look at the results threads of what people did for their routes...there's a ton of different routes. That's what makes it so fun. Not everyone is doing the same, precise route.