Thanks @inkwitch. It will really look great. Imagine a wall paper like this just you open your bathroom door. Your kids will never say NO for bath :) They will just feel like under the waterfall though :P

You can go for hard natural flooring for your common areas like hall, dining and stairs. For the rooms its up to your budget. There're so many choices like wooden flooring, Vitrified tiles. Marble flooring. For the bathroom you must go for anti skid floors which have there own specifications. For bathroom wall tiles market is full of choices .You can select as per your choice. About the colors in different areas, you should choose light and bright colors for your common areas. For the rooms, you can definitely play with different colors depending upon the who is accommodating the room and the interior theme. You can use wall papers and decals to highlight one of the wall in all the rooms.

The sheer curtains looks good. The thick curtains can be changed into a plain one (neutral grey maybe) instead of a patterned one as it looks crowded. The tv can be wall mounted. Remove the decorative items kept on the tv unit. Reposition the black loveseat to near the sofa at an angled position. The cushions on the sofa needs some colors. Maybe you can match the colour of the cushions/throws to a painting . Painting can be hung on the wall above the sofa.

good morning Rajbir kapur, instead of having a colured wardrobe try a mirrored wardrobe that will reflect and make your room look larger. but if u want a colour to go with ur walnut furniture then go for a beige or off white( creamish) laquer finish on the wardrobe beautiful in look and easy to clean. nowadays u can get wood panelling done on mica sheets . get a beige or fawn or off white colour mica done on your wardrobe( the doors etc) also the bathroom door do the same as ur wardrobe. .. wood panelling looks great behind the bed ( on the whole wall) but u already have dark walnut doors so u can just add panels of the wardrobe colour on the doors ( as in continuity contrast) . place your tv on a wall paper done up wall, or the wood panelling, or go for beige coloured stony brick wall behind the tv. will break the rooms colour cordination and make it look wonderful. have abstract or straight sleek cabinets below the tv. using the same laquer finish ( like on the wardrobe) hope these lil tips help u rajbir ji :)