We are thrilled with our layout and have had two people want to bring people back over to look at it for their build ideas. I'm so happy! Our kids are 7 and almost 11. We don't have any formal spaces. Downstairs we have our kitchen, breakfast/dining and living/wet bar area all open to each other. Our room is downstairs. There is also a guest room with its own small bath. Through one area is the half bath then a set of doors that contains our pocket office and the laundry room. My husband's man cave that has its own exit to the back porch and the wet bar are off the living area toward the back of the house. We have the playroom upstairs, along with the kids' bedrooms. My exercise room is up there too. So pretty much all adult spaces are down and all kid spaces are up. LOVE IT! My husband's sister's family's house has the adult-down/kids-up thing going on too. They have six children and are busy busy busy. It works wonderfully. The kids range in age from 5 to 17. It's wonderful because when they have people over, they have their own space upstairs and aren't all over us downstairs. And when we have get-togethers, the adults can be down and the kids can be up (or outside)! Yet the space downstairs is very open and family friendly so everyone can be together at once too. We can't wait to move into our house. I'm really liking the flow of the space as we walk through the house.

Am I the only one for which the playroom concept hasn't worked well? In our last house, we had a daylight basement and I painted murals on the walls, made a castle playhouse in a corner and put a swing up in the beam. They did love the swing, but if I wasn't down there, the toys just migrated right upstairs and they were with me. For flooring, I would look at some of Tarkett's no glue vinyl. It has a cushion and has the roads for driving cars. I put the glow in the dark stars floor in my youngest's bedroom. Spills wipe easily and it is easy to change as they grow. I chose this for my oldest two son's bedrooms and it looks like punched metal. Very cool. Remember that if the toys are all over the house (basement, other rooms for games) you will end up chasing them all over the house. I would want to consolidate storage. I really prefer laundry baskets for most toy storage. It allows for easy change and the dump factor is good, while not being deep like a tradional toy chest. My youngest is now 6, but when they were smaller I kept on of those bigger Little Tyke climbing things in the room. See if you can hang a swing from a ceiling beam. By far the best indoor toy. You just have to keep "stuff" out of the swing zone. The blackboard paint sounds fun. You can also leave the windows bare and use glass markers which just wash off. I have found child sized tables don't always allow for enough room for projects. I have a round coffee table which has small chairs I've picked up different places. If I was going to do it again, I would buy a kitchen table at the thrift store and cut down the legs to use as a craft table. It would wipe easier than my coffee table. If you do use any type of bookcases, I wouldn't have them project out from the wall. Be sure and attach them to the wall with L brackets to eliminate the tip factor if someone decides to climb. And mine always have climbed. I made our inside playhouse out of a 4' x 8' piece of plywood. Cut in half and put at a 90 degree angle with L bracket, it went right into a corner. Since I had 2 boys at that time, I cut it so it was shaped like a castle and painted the wall corner to match. They would crawl in there with pillows. At two, I can't think your child will spend much time in there alone, so be prepared to make a corner for yourself with a rocker or comfortable chair. I would also just pick an easy decorating theme. Primary colors is the easiest. So much stuff is really cute, but they grow very fast. A four year old just isn't thrilled with those bunnies like they are at two. I've seen the splattered paint floor idea. You have to leave the plywood subfloor bare and paint in and seal. I wouldn't care for it unless the paint splatters were planned. As part of the decorating, I would pick a spot for a growth chart. Put in on a board or something, so in case you do end up moving you don't have to cut a chunck of the drywall out. I knew someone who actually ended up having to do that because she couldn't leave the pencil marks behind. I had to paint over ours when we moved. Sigh. Have fun! Gloria

Oh come on! 10 years old and he has to be erased and banished to his room? The OP wanted to renew this room as a family room, not as a formal living room. In my books that means comfortable, welcoming and meeting the needs of the family. In this case, lego is his thing, mom is onboard and that should be the basis of the design plan.

Since the dining table + play area will likely be changing over time, I'd put the large piece of art over the sofa, where it has the best light. For the dining + play area, I'd suggest installing a picture rail at ceiling height, then hanging the pictures from it. That will let you move things around as your needs change, without filling your walls with holes. Maybe row of black and white photos, not too small, would look good across that wall. You can buy all sorts of systems and hooks. https://www.decoraid.com/blog/best-picture-rails