I'm wondering whether Clannad's town is based on a real location? For example, Air's village was inspired by Kami, Hyogo whilst Kanon's city includes locations found in Moriguchi, Osaka coupled with the atmosphere of Sapporo, Hokkaido.
Hmm...
Kanon = Large city in winter
Clannad = Suburban town in spring
Air = Village/small town in summer
Nice pattern