Hello again and thank you so so much for all your comments and suggestions. I read all of them and I visited our architect today. This is what we came up with. I think it is also what @nmshea recommended. I think this looks much better and is what we wanted. I just want to mention that we live in Cyprus where it's very hot most of the time so we need the big balconies and double doors. Also the small bedroom will be eventually a kids bedroom and not so much of a guest room but it's not that important now. So this is the plan with the last changes made. What do you think? Do you prefer L-shaped sofa or a 3-seater and a 2-seater? Thanks again to everyone who has commented :)

A vertical column radiator would indeed be a good option, and I like the anthracite idea. Alternatively, if you could find a traditional tall victorian radiator (may not be easy to source) and finish it in a bronze/verdigris, it could work really well with your dark mint and would be a real statement! Your staircase is lovely, and I would go with a contemporary striped runner, white painted sides and a simple rod.

Try farrow and ball elephants breath

How about adding a nice wall light perhaps as there are many nice decorative ones for you to choose from and could be a good solution as offers decoration and style at the same time! Not sure what your colour scheme is so if you add some pictures when you get chance to it might be easier for people to make some suggestions as to what to add. If you want to have a look over our wall lights these can be found here: http://www.thebulbco.com/led-interior-lighting/led-interior-wall-lights  Not sure about the mirror option though with you mentioning daylight shining directly onto them as if you have a mirror there you may end up getting dazzled all the time!!!!! Hope this helps :-)