I love the simple trim around the edges. Installing your own shiplap can be super easy! This is a great tutorial by Table & Hearth for how to install a shiplap planked wall using simple plywood underlayment.
Lofted beds with walk-in closet underneath. Good when you're short on bedrooms for all of the kids. Loft beds and instead of a closet underneath, it could be the kids "rooms" for private and quiet time.