Thank you both!
Great question! Yes, first of all I won't use styrofoam for the roadbed. I'll use plywood or OSB for that with homasote on top. To not use so much wood and provide for a grade between towns, it will be an open grid. I have built layouts using either open modules like this one and the L- girder. I like both. If I knew we would stay in this house until I am not able anymore or pass on first, I would go with L-girder, since my plan is a walkin affair. However, we have moved before, so I may make modules that would be easier to move. You can see my plan in the link in my signature line.
I like cutting foam for scenery contours, then cover it with something. The Woodland Scenics plaster cloth is something I'm trying for the first time, so this is a trial run to see how it goes. The same goes with scenic features, I'll use methods I know and try some new ones as well.
