I recommend a vent-free propane or natural gas burner and log set in the fireplace. It will keep you warm in the fall and winter months. It’s great for when the power goes out!
Hand showers are great because of the ease of cleaning the tub and shower walls. They’re very inexpensive and easy to install.
Use wall mounted faucets in a small bath. This can save a few inches compared to where the faucet would otherwise sit on the counter.