Great idea, Lee. Even though you have said that you love to watch the trains roll, I would encourage you to consider another idea. If you haven't tried true operating sessions, you really should. I thought that I had it all figured out but after I was invited to a couple 2-rail operating sessions, I was hooked big time. I thought that I had experienced it all, but after this one operating session, it hit me...this was the most fun I have ever had with a model railroad.
The two railroads were very different in a sense. They both had very long single-track mainlines with lots of passing sidings. One was built more around a concept where local crews switched factories in their small towns or industrial areas and then a regional freight would come by and pickup strings of cars that had been picked up locally and drop cars destined for local sidings. I thought it was fun doing the local switching, but the regional way freight was a total blast. I got to see the whole layout and interact with all the crews. It was in four separate rooms in the basement.
The other layout is enormous! It takes 30 to 40 people to run it. As close to running a real railroad as you can get. Fast clocks, dispatcher in a separate room, make up your trains a car at a time, modeled after real towns in NE Iowa and NW Illinois. We would run for two hours, have lunch and then run another two hours and when it was done you wanted more. This layout is in a 4,000 ft basement built just for it (no house over this part of the basement) and is on 3 levels with hidden storage yards and etc.
Some of my friends were nay-sayers until they tried it and now they are also hooked. It may not be for everyone, but I think it is the ultimate.