The color helps, and the gaps here and there, make the boards look to me like milled lumber that's been set out to the elements long enough.
Even around here (eastern PA), in a year's time, an untreated pine board will go silver-gray, and warp/cup/shrink, and we don't have too much in the way of extremes.
You might want to vary colors, too, as you add buildings, and have one or two painted, and then fade the color. Red would be good, just for barns around here, because you'd have cattle. Those slaughtered for meat yield the blood for the color, and those kept for milk give milk for use as the base for the paint. But there, too, in a season, it would fade and weather, and have to be renewed every season.
I look forward to seeing a whole town
Prost!
Brad