Hello Latai, I think you could definitely opt for some colour on the far wall.. This would accentuate the curtains and the feel of walking through into another more intimate room than that of the dining area.. What I would say is that you do need to look at some re-configuration.. You have a very light sofa and all the dark furniture is over to one side... I am not detecting a specific culture feel but nonetheless can be a very nice room with a little rework... So take a look at see how you can integrate them a little more, so they function but also sit cohesively as a relaxing living space. You could try to move the back sofa against the wall further along. Perhaps have one of those display cases at one side in the corner behind the sofa.. Put the plant on the little table and maybe have that at one end of the other sofa? What about having a mirror hanging on the back wall to throw some light back into the room... Where that little grouping of pictures are... They are a little small for that wall... Try placing them somewhere else perhaps... It's difficult to see from the angle of the photo's but do you have a coffee table or a low ottoman between the two sofas? If not why not move the low table you have (with the matt and two ashtrays?) That could sit between the sofa... Then the other cabinet can be moved away slightly and then the table with the Television? has a bit of room... Thus all the dark pieces are well integrated into the room and not all grouped together.. Colours that would work well with the wooden dining area, are Terracotta's and Rust colours to compliment the dining table and chairs... Accent that colour with some cushions to add to what you have on the sofa's I'd have a plain linen table runner (nice one's at John Lewis) They are quite long and hang a little over the ends... With the cushions..don't put them all the way round the sofa, but have 1 or 2 together and a throw or two could be nice as well to layer the colours... I like the floor colour and that can work as it is.. I move things round all the time, and I'm always amazed at how you can transform something just by putting it somewhere else.. Lastly... I don't see any table lamps.. Perhaps 1 on one of the little tables with the flowers... : ))

what colour on walls if whole cupboard is of dark purple

You could do a warm or cool gray, navy blue, soft pale white, the same green. Really up to you.

I'd suggest dark red curtains if you need curtains at all -- the windows are beautiful as they are, and I'm not sure whether some kind of blind might not give you the ability to darken the room when you want to. On the wall, if you are real fans of any movies or TV shows, three big posters would be fun. Otherwise, I would still suggest using three pieces of art there of that size, all equal in size and somehow relating to each other. Three floral works, or three works in the same style, perhaps. I think a large plain textured rug in a light neutral from one of the cushion fabrics would tie the space together well. You might also consider a lovely low coffee table on the rug to lay out your snacks and drinks for serious media nights.