One possibility would be to swap the living room and the dining room. Since the current living room is larger than the current dining room you could still keep some comfortable seating (couch and upholstered chairs?) against the front wall for a keeping room/dining concept. Then your new dining areas (kitchen and dining room) and living areas (living and drawing room) would have good flow between them, which would work well both for family and entertaining. You could also add some builtin bookshelves in the drawing room or new living room to create a library area to add another fun element to the living areas. These bookshelves could be against the long walls in the drawing room, around the window with a window seat in the living room (former dining room), or built to create some separation in the open area between the drawing room and living room/stair area. Your plan seems to show some sort of builtin there, but I'm not sure what it is.

You could also bring in some texture with bamboo sticks or decorative branches and help balance a bit the height of your room with small scale furniture. Spray paint them if you find the perfect size and shape but they aren't the color that you need. Ikea carries white decorative stalks for a very good price. the ones in the 1st picture hold well with small kids around and you don't need a vase for them. there are washi paper or crinkly paper floor lamps with a soft beautifully diffused glow For a budget friendly version check ikea or target http://www.ikea.com/us/en/catalog/products/80028552/

With your original pictures - I agree with larger rug. But I don't agree with comments suggesting the rooms are monochromatic. They are lively indeed. I think you are just missing some accessories! Art work on the empty walls - even just a single large dramatic piece is in order. In the bedroom on the white wall, in the living space behind the sofa, in the greenish bedroom behind the two beds. Those are instant areas where you can improve. But I think your spaces are lovely and well put together. Also I agree with the comment about table lamps - some of those would really add something, and your coffee table looks so empty - maybe just one gorgeous bowl, or stack some books. These rooms are 90% done in my opinions, just need a few finishing touches. Some of my rooms come out like this because the clients are not willing to pay for those last few finish items or feel they can do that part themselves...

Love the armless sofa-bench! Try using it in the center as a "cross-linking" piece between the sofa and chairs. That way people can sit on both sides of it, conversing with the sofa people and the chair people. Put the chairs where it is and use the side table from the left of the pic, or the one with flowers, between them. You'll need one huge rug to anchor the space or two smaller, and very similar ones, to put on either side of the blue sofa-bench. The other two side tables are too tall and too short for your seating pieces, so ditch them. Use your coffee table between the sofa and armless sofa (18" away from each of them.) Here's a chart for judging table and lamp heights as you'll need to work on that for balance. Please try this arrangement, and post by commenting and using the Attach Images button to add pix of the update. We'll tweak it on out from there.