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.

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...

One option, I would get a very large rug so that all the chair legs and at least one corner of the sofa is on the rug. I think I would also bring the table set away from the window a little more. I think there is enough space to place the two-seater opposite the table in front of the window. or bring the table forward toward the kitchen ....... With the sofa centered to the large window. They probably will not be opposite each other, but at an angle which is still ok. They might seem more functional for the table set to be closer to the kitchen. Another option is two rugs in wide runners. Creating a walkway through the center of the room. Still thinking the sofa center of the right window. Just some ideas :-)

Great space, but narrow. How about the couch where the two chairs are, the storage piece under the artwork, and the two chairs in front of that light wall? If you need more seating, put the chairs across from the couch, and add another couch the same size at a right angle. Your area rug is a bit small. The wing chair should move away from the window, perhaps angled into the window/wall corner.