"I suppose it throws up the contrast between farmers and fishermen.
I wonder how this solar-lunar contast may have affected the belief systems/spiritual identities of prehistoric communities."

Exactly ,one solar and the other lunar may be a bit romantic and simplistic but it's a possibility .Does lack of shell fish middens in the hills suggest a wee chippie and no tesco ?.The RSC's are often considered lunar but are usually well inland , I'm not too sure about that , there is quite a good case for a solar centered approach there. The two communities were guaranteed to have fought like hell on saturdays but intermarried too and got on fine when those further afield mussled in on the shell fish or deer.