John,
Yes, it is hard to know what you may want on a first layout that is more than just circles around a Christmas Tree or on a sheet of plywood. Some folks like a lot of switching cars at industries and in the yards. I find a little of that okay, but not a steady diet. I am more of a railfan, wanting to see a train run through multiple scenes Some people like a number of independent loops and have several trains running at a time. Of course like most of us, you want to replicate scenes and train movements like you have seen in the real world; ie the subway. You are ahead of many since you realize you can't have it all, Grand Central Station would look odd without a whole set of skyscrapers and how do you fit that into your space with Anthracite Mountain running?
I had two large passenger engines and two sets of long passenger cars I thought I could run on wide 072 loops while having other track for mountain hauling. Well you may have seen in my topic where I discarded that idea, sold the big engine and long cars, and am going with just the small ones. Nothing larger than a 2-8-0 Consolidation and first generation diesels, with 15" passenger cars.
Yes, the trip to York is a long trip for me too. I have gone twice, but didn't go this past October. We should join up and go together sometime.