As I see it, I think that in N scale it would be an overkill to 3D print it, then having to carefully paint it just to get that tiny amount of relief which will likely not be readily visible by naked eye from a normal viewing distance. I guess maybe if the relief was greatly exaggerated, it would be easier to paint and also to notice when looking at it. If this was my project, I would just print it flat on paper using a standard color printer.
If this was done for 0 scale, then 3D printing would make sense as the relief would be clearly noticeable.