A glazed door would allow more light whilst still providing privacy. I would be replacing the cabinet with a smaller one that is a little taller, then you don't have to hang the TV on the wall. A bright rug and a large colourful print above lounge suite will also make a big difference.

Can you please post pictures from several angles?

Wow, that house is WAY to big. How on earth do you clean it? Why not have outdoor entertaining on the back deck? This would incorporate flying fox to a cubby and play equipment down the back yard. In the summer perhaps a collapsible awning for during the day but at night just candles and the stars to keep you company. If the weather is too cold you could provide a pile of crocheted lap rugs or fur or old blankets to get the cottage or french look. I suppose then your dining furniture would need to be a style to suit - maybe more relaxed or boho. Anyway sounds good fun - oo I forgot to allow for the outdoor fireplace (stone or brick) preferably. I notice you said any ideas would be greatly appreciated so I will press on regardless another day.

You have a huge room, with lots of options and opportunity. So much will depend on the size of your furniture. Some furniture is made for apartments, like a lot of the stuff from Ikea, and has compact dimensions. Other furniture is made for McMansions so is generously proportioned, and sometimes oversized. Find what you like and are comfortable in before seeing how to work it in the room. If the room is only going to be for TV then make it the focus, but if you have views, and you will use the room for other things then the position of the TV is secondary. Don't buy any furniture until you have measured it carefully and planned the room layout, knowing where your TV will fit. Best of luck, Dr Retro of Dr Retro House Calls/Dr Retro Virtual Visits