its the sofa that stands out, while the lighting is very beautiful, its subtle and compliments the rooms very much. the horizontal partition on one side and the lighting display both make for a beautiful backdrop which which makes the seating area stand out.

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.

Charcoal sheet is used for decorative purposes. It comes in 8x4 and 8x2 feet panel size. You will get them in most plywood and laminate stores.

That explains his opinion. Your description until now was for outlay doors. Slideline 16 is capable for 50-60 kg and 18-24 mm doors only. As I said earlier, not a big fan of bottom running sliding systems. Hope it works fine for you. Steel decorative strip is possible . But avoid deep cuts on the door that would increase the chances of bend/warp.