There is contrast between the traditional furniture and the focal point of the floor which pops, draws attention. I would recover the sofas in cream colored soft fabric - suede. I would leave the curtains grey, and put down a large neutral area rug. The edges of the room would show the pattern of the floor. I would color the wall and add texture to it, but not too dark as the room will appear smaller. Add a picture and put a nice plant holder, large vase in the left corner of the room - an oriental-style vase. Or, a cream-stripe fabric on the sofas. You could go soft or bold in this room - depending on your taste.

I think a comfortable distance between the island and the counter is around 42". It seems that you have only 30" between your cook top and the counter. I might be a little too tight. The wall between the entrance and the kitchen could be 4' long instead of 6', you would then be able to move the island a foot which would give you more room between the cook top and the island. Could you switch the location of the toilet and vanity in your dad's bathroom so your enter facing a vanity instead of a toilet which is a lot nicer.

So sorry.....I see the dimensions on your floor plan now....oops. It was middle of night here. You have a great place with lots of options. I will try to find a picture for you, but here is what I would try. TV on left wall. Put it on a console table 20" to 30" high, or wall mounted with a wall mounted console below. TV should not be too high or too low for viewing pleasure. The main walkway to the balcony will be on left side in front of TV. To see how the arrangement feels, Try your sofa on the right wall facing the TV. Then put one of the chairs in front of the sofa with its back to the glass and the other opposite of it with the back to your entry. If you feel this arrangement is too far from the TV, a sofa table can be used behind the sofa to move the whole seating arrangement forward. Then if this feels good, you can add a rug. The rug should be at least big enough that the front feet of the furniture can rest on it. You will then need tables on the sides of your sofa. You have the choice of a coffee table or what is called "cocktail ottoman" which you can put a tray for drinks and food on, but still put your feet up. That is always nice when watching TV. If you like this arrangement and go to buy new furniture pieces,get the chairs on each side of the sofa that swivel so the person can watch TV easily. You need to think a lot about what colors you will use in this houses if any rooms are done, take some cues there. It's a big decision that will influence every purchase. Find a 3 color combo that appeals to you. Again look on Houzz at the living room pictures. Post some here that you like.

You can work with your currant wall color or go more yellow - that is up to you. If you do decide to go more yellow. get some small inexpensive sample bottles at the paint store, paint some poster board and hang it on a wall for couple of days because getting the right buttery yellow can be hard. A soft yellow and lavender is pretty together but I also like the sea green. When you said a combo of modern and cottage - that made me think of beach cottages, which often have soft colors (including sea green) and unfussy, calm interiors. You can put a large painting up if you have the wall space for it. Many bedrooms have tall chest, dresser mirror, tall headboard and big TV, all which take up wall space. If you can hang the painting without it being crowded by any of the things I mentioned, it should look very nice. If you wish to do a curtain fabric treatment to a wall and you have the vision of what you want - then go for it. I had a friend who did that in collage - only problem was the yards and yards of fabric needed got rather expensive. So, I would start with finding bedding you love. Simple white is good, and not too expensive. However, you might find something else light that you love, or a quilt or throw for the bottom of the bed and the colors and shades might lead you in a different direction for wall color or accents. So bedding first, then curtains, then see how your wall color is and then add accents and art - although your painting can also be an inspiration for colors.