I would scrap the mainline connections to Eastwick and Westham in order to preserve the Inglenooks switching operations in those two areas. Also, I'm not sure what the purpose is of the outer-main passing siding hidden under the mountain? Being under the mountain this track cannot be used as a fiddle yard?
I don't know what the codes might be and I don't know about frostline in your location but wrt the bathroom, there are macerator toilets that pump the sewage through a 1" line and can even pump up to iirc 10" head. They were designed for basement bathrooms in structures where the sewer connection is higher than the basement floor. Could be a way to simplify the sewer line to the house.
Lew, I added the mainline connections at Eastwick and Westham thinking a passenger train serving either town doesn't have a passing track to run the engine around to the other end of the consist for a return. Other than that, I agree with you and would prefer to not have these connections. I noticed that they give me a third circle mainline around the layout (O72 min through turnouts) just sharing the bridge, so perhaps a third train could run if I protect the bridge with signals and etc.
Agree, the passing track is an add-on, not sure what it does for the layout plan, perhaps nothing. I might delete this feature, and yes its not a good place to add/remove cars after all. Perhaps I would want to stage a train on this track?
I am OK on the water/sewer connections, they are close by and easy to tap into from that corner. Sewer drop is OK. Thanks on that.
Tom, the minimum curvature is O108 for the yard tracks at that 4.25" center spacing. I am thinking that would do, but have no experience with very large scale equipment. If a problem in the future, there is room to pull the yard out with wider curves at about O120 if needed. I don't suppose there would be much need for a Big Boy or Challenger to be positioned down these tracks? Thanks.
Sometimes we see a locomotive "ready track" (not sure what correct name would be) at engine service facilities for locomotives serviced for an outbound train, ready for the call: