I've built several N-scale layouts over the years and love the 2' depth one can achieve in that scale. I don't have any words of wisdom other than to wish you encouragement. A lot can be done in 2x4. Even just a loop with a passing siding and a few industry sidings can make for a very effective layout.
This is old track plan and is larger than 2x4 obviously. Like most of my layouts it only got to the benchwork and some track stage. I was able to get away with two tracks because the largest equipment was an 85' scale passenger car but having some opportunities to run mainline trains and some operations or even just display of some cars on sidings makes for an interesting layout.
