Long term relationships are not to be entered into lightly. Living together for a while before making a major decision is generally a good choice. It's the best way to know if it's gonna work. Which explains why I didn't touch the back wall of our living room for six years. We were into the idea but, built-ins are a serious commitment.
I first designed a picture window with an arch echoing a detail seen elsewhere in the house. The original Mediterranean/Deco transitional elements made Moroccan inspired plastered built-in shelves with a bench an easy leap. Though, as I applied drywall to the 2 x 12 framing I got a "Flintstones" comment from a friend who should know better. A few days later as the top coat went on, he ate his words.