A few questions: I want to run a passenger and freight operation in a single layout. I want to include a power plant with coal to go to it, and a passenger opeation spanning multipple cities. One city I want to be large, about 5X5, very dense. I would like to incorporate water as well. (at least a little) THe passenger cars will be about 4-5 deep powered by a medium sized steam loco. I have about 8X8 to work with. Would an O shaped duck under be best?