Post over in Home Decorating. Lots more activity there, and people who are real whizzes about this sort of thing.

Perhaps you could wall mount the TV on a fully articulated arm either side of the FP, but higher than mantel level. It can be lowered and tilted down for optimal viewing and the sofa can float facing the FP with a pair of swivel chairs right and left of a coffee table. What is outside the windows? They look quite boring compared with the FP. Could they be replaced with a set of French doors leading to a patio or porch?

@Beth Yes I like those blinds a lot in the last picture, and that couch is the color I planned to buy. Do you think curtains with these blinds are too much? I have curtains in my house, and our old house had blinds and curtains, and I really liked that look. We live in the city, and have lots of noisy (and nosy) neighbors... I love the roman blind over the sink look too... Since these windows are all in the same room (except for bedroom) should it be unified with the same base idea (like all have blinds, but some have curtains too?)

@Sophia Davies a rule of thumb is to think about the walls last. First think of function. Then choose the furniture that best suits the function. Keep the lines simple, clean, classic, time-tested....the little black dress in the furniture world. Nothing bulky or excessive, and no sectionals for your first furniture.  I'll share some advice I would usually give but am not sure is appropriate for you and this space. The advice would normally be to go shop in an outdoor furniture store and get really good outdoor furniture for your first furniture. Good quality is less expensive. The furniture is light weight and easily moved. If friends or pets or children barf on it or worse, it can be taken outside and hosed down, or the cushions replaced. Then a decade later when you have your first house and can afford to or want to buy really nice indoor furniture you get a two-for... Indoor furniture and your old furniture becomes your patio furniture that none of your friends think they can afford.  You know, another good source of furniture is grandparents and parents wanting to downsize. I would love it if my daughter wanted some of my furniture. And finally, find a furniture restoration place near you and ask about sources for used furniture of sufficient quality to restore. You can find some really special pieces you will treasure all your life. I got some great tables at an estate auction.