One more option I can think of for the couch. This is what I was originally going to do, but then started worrying that it would be too closed in. Arghhhh

I found a pic that might give you some suggestions for your room.

The room shows a table in the foreground and you might try a round table; you need three feet around all sides for chair and walk room, so it might fit depending on size of table, or do square as shown.

Comfortable Luxury · More Info

In the middle is a pretty round entry table with plants on it, which visually divides the room....there is also a console table in front of the windows on the right that could be converted into a desk are; if you want privacy then three fifth curtains across the window with the upper two fifths of the window with out a curtain......

YOu could do a pair of sofas with chairs on the end on an angle as show in the pic, or an l shaped sectional, or a chaise sofa facing the TV for great viewing. All of these would work.

The Boulevard · More Info

Love those rooms! Thank you! In my mockup the table on the right of the room is an old 1940's wood booth which is what we have for dining right now. A round table is a great idea for the future when we can replace the booth.

I like the idea of dividing the room with a round table with plants on it.

So it's ok to put a desk right in front of the sliding doors? Privacy isn't an issue since we're 1/2 mile from the road with no neighbors. The sun does blast through there in the winter, though (it's a passive solar house).

Do you have a preference for one of the types of couch set ups?

I think the couch would be better flipped the other way with the opening towards the entry and blocking the sliding door. The other way you'd have to walk all the way around the couch to sit down which would not be fun.

Putting the desk behind the sofa is a good idea, however it needs a computer with monitor which might look funny? Right now I put a long vintage dresser behind the couch which stores our office supplies. Your design is so much more open, it would look a lot better. I wish we had another room for an office!

If you can do without a sideboard, put a computer armoire at the end of the dining area. You can use a dining chair as your computer chair when working there.

Vermont Heartwood Modern Office Armoire - Modern Office Storage - Modern Office · More Info

The fireplace is such a presence in that long room along with the long wall of windows. What if you placed your sofa to the right of the fireplace in the L shape that returns on the window side. The sofa will face the TV. Place two small accent chairs facing the sofa. The chairs can swivel if you want to use them to watch TV. Place a library table behind the sofa dividing it from the dining area. Place comfortable chairs in the area in front of the TV with a coffee table. Build in the desk in the TV cabinet so that there are no computer or lamp wires exposed in the glass sliders. You could also fit two apartment sized sofas facing each other perpendicular to the fireplace. I also love the idea of a round dining table. It will really soften the long anglular room. My apologies for not having a floor plan drawn up but will get one if this concept appeals to you or if my description is difficult to grasp.