Seems to be a basic problem with Old West games where there are factions or "posses" - it ends up a sordid free for all and nothing like what might have been in a 'real' world. I think the solution is some careful scenario design with restrictions on the players and nasty negatives for targeting the wrong group. But wargamers being warmers you might still have challenges. The right rules still haven't been written to sort this out - not that I know of any way.
But I agree, very nice buildings - though I wonder why the church so much a different color than all the other buildings. Do like that you did a train robbery game.