This will help get some light into the middle of your space. http://www.westelm.com/m/products/overarching-floor-lamp-antique-bronze-w890/?pkey=cfloor-lamps You could also do end tables or a console behind the couch and place table lamps on either. It doesn't look like you have any seating near the edge of your space and your existing lighting seems to be positioned at the edges of the room. So I'm not sure if sconces would help much.

I want a simple arch design between hall and living room

Hello Devaraj, You may want to try L107 major and 8218 as an enhancer . Asian paints shades used as reference. Thanks, Nitin CORNERSTONE DESIGNS Bangalore

Also please replace the heavy maroon drapes with a lighter treatment. Maroon against parrot green is a really bad combination for interiors. Now that I am looking at it on my system, I confirmed that you also seem to have one pink wall.. If you are partial to strong colours, paint one wall a medium cobalt or jade green if you must, but leave the rest of the room off-white. However, I get the feeling from the photograph that there isn't enough natural light in the room. so it may be preferable to go with mushroom or sand on one wall and leave the rest of the walls off-white. And by that I mean a plain base white with just a touch of ochre stainer or turkey umber which still makes it look white, but warmer.