Great ideas @havingfun! Thank You! It's funny, we started physically moving some things around down there, and I'm starting to think the TV should indeed go on the far wall. I'm just worried about it creating a black hole at the end of this long room. Are you suggesting dividing the room into two sections? Like a TV section and a fireplace section? "face couch or appropriate chairs towards the tv. appropriate chairs or couch to fireplace" and then a rug in each section? I like Bohemian, vintage, rustic, industrial styles I think. I liked the first and third rug you suggested. Maybe light bright rugs and warm darker furniture? We really like the idea of leather sofa/s, like the kind with the nailheads. We have cats and friends, so any anti-stain, non-fur grabbing furniture is what we are looking for.

I'll second the articulating mount for above the fireplace. It's your best solution IMO. Pull it down to watch TV and push it back up when you're done. I have my tv over my fireplace and I've found it very comfortable to watch. But we have it mounted low and angled downward, and our seating area is ~14 feet back so the angle isn't at all uncomfortable. Without seeing a pic of your actual space with measurements (how deep is that living room?) it's hard to know if your seating area will be far enough back to be comfortable without an articulating mount - but I can promise you such a mount eliminates any potential problems.

You do not give any measurements, and that makes it impossible to envision. Measure each wall in the room. Measure from a corner to door and window frames. Measure the width of the door and window openings. Draw out the measurements on paper so that one foot equals one inch. You don't have to use graph paper, but use a ruler to keep the scale accurate. Position the door and window openings as accurately as possible, and if a door opens into the room use a curved arrow to show which way it swings. When everything is drawn out look for obvious pathways. Since you describe this as spacious, there should be room to walk around furniture groupings. Next measure your furniture—sofa, chairs, tables, bookcases, TV, etc.—that you plan to use in this room. On a separate piece of paper draw the outlines of these pieces at the same one foot equals one inch scale. Label each furniture piece and cut it out. Now you can lay these furniture pieces on top of the room floor plan and move them around till you like what you see. Here is a picture of one room plan. As to where to put your TV, many people put it next to the fireplace so as to keep the focal point on that wall. If there is not enough room there choose another wall. Don't place the TV in front of a window, especially if you watch TV during the day, because the backlighting causes eye strain. All the guides I have recently read say the bottom 1/3 of the screen should be at eye level of a seated person. These guides also recommend sitting much closer than I would have thought, and that distance varies with the resolution of your set. For instance, a 40" 1080P HDTV is best viewed between 5' and 8.3' away, whereas a 40" 4K Ultra HD TV has optimum viewing between 3.3' and 5' away. Here is the link to that info. That seems ridiculously close to me. Should you have no suitable wall for the TV consider using furniture as a room divider to hold the TV as below.

I like your proposed arrangement. Looks like you could add a t.v. on a swivel mount with a small console underneath to the right of the fireplace. As a general rule, the rug under the dining table should be 4 feet wider and 4 feet longer than the table, so it seems an 8x10 would best suit the table when fully extended.