Congrats on your new home. I think you've got a good start. I like your sofa - it looks comfy and is well proportioned in the room. A fun shag rug and some bolder, graphic pillows would be my suggestion -- or another colorful rug that might brighten things up. You could also add a starburst mirror on the wall next to the windows. I would put a plant behind the yellow chair and bring a throw pillow that coordinates with the ones on the sofa to tie it together. I would also put a long console table behind the sofa with a single lamp on it like the below photo:

I'm intrigued by the concept of new build in MCM style. Are you in CA?

lamp on end table (unless cat plugs in). I really want to say put TV over dark console and get art for over fireplace, but I imagine that ship has already sailed. need some way to tie in yellow chair, though -- pillows on couch? make the lamp have a yellow base? yellow patterned throw, or dish for coffee table? also, pull the chair forward into a more believably conversational distance, and put a floor lamp behind it.

How fun! I know of a few builders out in Palm Springs that are building new MCMs and I love this trend. What color is your front door? I'm remodeling a mid century modern and am choosing a color for our slab front door. Thinking orange but not sure what shade...

Pipdog - Mine is a neutral but others in the neighborhood are bright orange, lime green (I once had a laundry room in SW Parakeet), and I believe I've seen some stormy blues used too.

I really like those interior shots! You might have good luck at estate sales. Sometimes, really nice pieces come up at these sales, because the kids grew up with that stuff and they're tired of it, so sometimes you can get really authentic pieces without spending huge amounts of money.

Your pets are adorable! I really like what you've done, but would suggest some pillows on the couch that have some yellow in them, and maybe you can source another chair on a venue like e-bay that won't break the bank. For your clean, spare style I would not suggest a console behind the couch, even though that's a very popular thing to do. Even though this style is very different from mine, I really admire the way you've done it, love how you did the photographs on the wall. Some art on the dining room walls and a carpet under the dining table would add a lot of impact.

lol, I saw the beautiful cat but didn't even see the cute pup until ingrid mentioned and I went looking.

Your place is great! How lucky to find such a neighborhood. If you look up modern mid century throw pillows on Etsy, you will have a lot of really unique ones to choose from that will go with the ones you already have. (I have to stop looking/buying as they have so many really fun ones)

I would get some Teflon glides to put under your casters so that they do not distort the rug, but that's a minor detail. Also, I would switch the "C" sculpture on the side table with the brass(?) armadillo on the cabinet. I really like the armadillo, but it looks too small on the dresser, and I think it might be appreciated more on the side table.

Lamps on side tables are nice if the tables are next a wall or if you have a floor outlet - otherwise you run the risk of tripping on cords.

I really like your room! I also would use a little more of the yellow to make it all look deliberate. In my minds eye I can exactly picture what I would place featured all by itself on your console/cabinet next to the fireplace: a large contemporary organically shaped blown yellow swirled art glass bowl.