Family Room Ideas

So I need some opinions. I spend a lot of my day/night feeding baby Hadley so I'm on my phone occupying my time. I am loving the houzz app that has design ideas. I also spend a lot of time looking around my house and showing Hadley different things (it's boring being a baby). So I haven't hung up anything in the living room (family room, same thing in our house). The couple that owned the house before us had painted their master bedroom a dark navy blue. I really do like that but the room is on the smaller side so it sorta made it look smaller. We had it repainted gray and love it. The couple kept and labeled all the paint they used and it's in the garage. I have been thinking about what if I painted the inside of the book shelf to add a color of pop in the very neutral living room. I do not want to paint the whole thing due to too many other colors going on in here. What do you think? OR I could paint it the gray color we have from the bedroom but I think navy's an IN color these days and it all started because of these curtains I saw from the West Elm catalogue (they do also come in gray though).

Here are some room inspirations I found after I thought about my idea. I took these from my phone and I didn't feel like cropping so sue me :)

this one is more like what I'm wanting to do minus the rug and more navy color in the book shelves.

this is my actual book shelves

The other issue is, I don't know where to put the curtains or how many I want/need. This is where you all come in! This is our messy living room (that's all James' stuff on the table for the record). The previous owners had curtains up where there are the rods right now (which could be throwing me off). Those windows do have blinds on them. The door has no coverings at all and there is a house behind us that MAYBE could see in but it's not a huge concern but may sway your decision? I'm thinking I want two sets of curtains to really get the navy blue coming out but maybe not? Where do you think I should put them? Over the door and over the right window? Leave the rods where they are? Just over the door? none of the above?! The book shelves that would be painted are right by that big window on the right. We are going to move that green/brown mirror over the fireplace to the hallway so don't let that sway any decision (feel free to suggest what you think we should put over the fireplace now.

This is the previous master bedroom color so it's a deep navy.

So what are you thinking? You liking the navy, or could always do a gray instead? This living room needs your help, don't let it down.