Mark, my personal opinion says adding a yard in the laundry room is too much trouble and is not going to pay off in the long run. I think your original idea to build some drawers or shelves to store rolling stock and manually build new consists is the way to go. If it were my layout, I'd probably add the hidden yard I mentioned some time ago, but that has it's own challenges with only 8" clearance, especially if you'd want to move cars around and not just store alternate consists.
