In my opinion, a cuckoo clock is a very detailed design, but you say you want a simple design for the room. When you say simple, are you thinking of no wallpaper, no wainscoting, and no accent color on the walls? It seems as if dark orange is a color you favor. I see it in art images and in your curtain color. If this was my space, I would paint all the walls one or two shades lighter than the beige of the sofa to keep the room as bright as possible because the room has no direct sunlight. I would paint the ceiling 1/4 (one part wall color to three parts white). I would use a satin or eggshell paint instead of matte, semi-gloss, or high-gloss paint. I see some discoloration on the wall behind the sofa where the brown color of the sofa frame has worn off onto the wall. I suggest attaching bumper dots or strips on the wood frame of the sofa (similar to the ones used to keep cabinet doors from making a lot noise when they are closed quickly). I would consider painting the sides of the column with the cuckoo clock brown to match the clock. I would do this to call attention to the clock. I would remove the orange curtains and replace them with floor-to-ceiling length draperies hung as close to the ceiling as possible to make the room seem larger and taller. I would change the drapery color to match the walls, perhaps in a muslin-like fabric, which is a casual fabric. I always take my art to a professional framer. I have conservation matting and museum glass used for my art. I would have the three images you have rearranged as a collage in a very large single frame with medium to wide matting between the images. I would have the mat and frame color(s) enhance the images, even if it is a color I might never have thought of on my own. I would hang it above the sofa. I would use the orange drapery fabric to make throw pillows for the sofas. You did not attach a photo of the flooring in the room. A medium tone floor is easier to keep looking clean than a light floor/rug or a very dark floor/rug. Other "Houzzers" will give you completely different ideas. Use the ideas YOU like and enjoy your home!

Try microfiber as it is easy to clean and take care of. If you are worried about stains, try an indoor/outdoor fabric like Sunbrella. I recommend Ultra Guard fabric protection in lieu of Scotch Guard. Stay away from loops and chenilles if you are worried about your dogs and their claws. Solid colors tend to show stains and pet hair, so try looking for patterns or multicolored fabrics. Hope that helped!

I would say a single sofa is most comfortable for sitting and It can transform the interior of our home. Recently I had ordered one single sofa from Oriental Creativity at a very good price. You can check this design. I am very satisfied with the purchase.

two basic issues your room floor is dull is that floor to floor carpet if yes then add a a smaller area rug under your table to get splash of colour, alternatively if you dont want to do that then add some colorful wallpaper behind the sofa. Where you have the table lamp add something taller like a modern floor lamp or a tall spread out palm plant. Take the table lamp and add to a side table if you have one. The second biggest issue is that you have a lovely modern sectional sofa and then you have paired it with a very traditional and very high coffee table that looks like it has marble inlay work done (cant make out clearly). This is not a good pairing. The coffee table is the right size but get something modern and a lot lower, a general guide to this would be one inch to 2 inches lower than the seating height of the sofa. As someone else mentioned an Ottoman that can serve as a coffee table in an alternate colour will also work. Paintings and wall art is something you can experiment with but unless you do something about the coffee table the room will continue to look odd in my opinion. Also some more shots of the room will help us get perspective.