Do not overlook the benefits of pocket doors. Be sure to use a pocket door frame that has metal stud channels. These frames will not warp over time. Your foundation, crawl space or foundation slab are also very important. Houses with full foundations should have foundation walls that are at least 9 feet 8 inches tall.
Bathrooms are very important.
The space created for the toilet should be at least 36 inches wide. If you can provide 40 inches, do so. The minimum width of the bathroom seems to work best if you make it 6 feet wide. Make the bathroom as spacious as possible and try to include a large pantry within the room, not in an adjacent hallway. Try to design the laundry room as a separate room if at all possible.