A question for you Warren: do you put all your different items on their own layers AFTER you have drawn everything or have you changed each symbol/ wall/ etc. definition to put them where you want them?
I generally place items on a layer well into the drawing. Like Plumbing Fixtures, I will at some point click a toilet or something, place it on the Plumbing Fixture Layer and then hit repeat edit an start clicking all of the plumbing fixtures. For Cabinets, at some point, I will right click and pick Add Group Selection and this will highlight all Cabinets. Then I change all Cabinets to their own layer. Most items can be left on their default layer like walls and openings. But items like Room Names, Detail Notes and other items that I do not want on any other Modes but for the Main Floor Plan, I place them on a Layer called "Main Drawing". For a note that I want to only show up on my foundation drawing, I place them on "Foundation Mode Notes". All of my Layers are placed in alphabetical order except for the three or four that I use most often and they are all at the top of the list