Hmmm,.. lots great ideas but as others said space is an issue. A few years ago I was planning a permanent layout but as the design progressed I encountered that problem, space. While I might just squeeze it in I wanted to verify everything. So before proceeding I started laying fastrack on the floor so I could get the visuals and see if everything operated as assumed. It was rough on the knees (even on carpet) but as I worked out the kinks of the plan it proved the space I had would not be satisfactory. It's been two years now and everything is still on the floor, the lady of the house is used to avoiding the tracks. I've pulled everything up a few times making adjustments for things like fixing derailment locations by adding a ten inch straight track between switches ( I found a 5 inch didn't do the trick). Added larger radius transitions into the loops and divided my yard so longer strings of cars could be stored. Then again adjusted to accommodate an easier grade to a second level. Buildings and structures sit on removable flats.
The point is having a layout on paper can look great but might encounter problems after its built and the redesign then may not fit the benchwork. For me I kind of enjoy the surprise of long trains appearing out from under my desk, then disappearing behind the TV console, only to pop out again beside the love seat, and as I said, I'm still just testing the design. Perhaps I need to build a custom house,..
