This is a huge mistake, especially with a non-climbing spouse. There's nothing more aesthetic in a living room than climbing holds bolted onto a makeshift wall covered with scuff marks and chalk dust everywhere. Are you going to need to move furniture around every time you want to use it? Are you planning on padding the landing zone? Where will the padding live when you're not using the wall? Do you really intend to turn your living room into a gym? There is no such thing as a "low key" climbing wall.

I've climbed for over 30 years and built several training walls - basement, spare bed room, and garage x2 - never once did I even remotely consider putting it in the living room.