I would advice you to go for all white and then have coloured art and accessories on the wall that you wished to have as accent wall. This way you won't be struck with one colour till your next repainting job. You will also have the liberty to change the colour pallet depending on your mood and season with just changing a few things like paintings ,cushion covers etc. involving very little cost and efforts.

Surbhi, The width of the room is not mentioned here but from the scale it looks like it is ~8 ft. Effective living area would be close to 90-100 sqft . Grey and darker blue may not a be a suitable palette for this area. However, the tiling is already done. You may want to go for lighter shades for the remaining areas like wall paint (try 8260 Asian paints) and maybe brighter contrasts for sofa and curtains. Bright pastel yellow or beige may be a good combination for upholstery. Thanks, Nitin CORNERSTONE DESIGNS, Bangalore

no

Wooden molding in HDF or Teak wood can easily be nailed directly on walls with headless nails. No need of ply or board at the back. Also don't go for POP moldings as they are not durable.