Something about your measurements of the spaces seems off. I can't see a 7.5' length anywhere in your living room. Double check your notations. If your family enjoys table games, the sitting area would make a nice spot for a game table and chairs. Otherwise, make it into a lounge or reading nook one or two chaises. I agree with TV between the windows. Try a sofa and four swivel chairs. Keep the scale smaller and use a 3-seat sofa to seat 7, Then squeeze in a pair of smaller chairs in the corners right and left of the TV that can be pulled out for viewing. The coffee table can have space underneath for a couple of poufs or stools to seat extras.

mumshelper can you post some pictures of the rooms in the home? How high are the ceilings?

In fireplace area, either a setup like this, with four chairs and center cocktail table or ottoman. Or I would put a three seater sofa on the one available window/door-free wall, the wall that has entry passage to bed and bath - and float the tv.

Brad covered this well. I had a single duplex outlet installed above all of my fireplaces, as well as 1x coax and 1x cat6 in the another duplex box. True I don't want a TV in every single room over every fireplace, but I wanted the option to. A picture or a mirror over the fireplace covers these. Something Brad posted (and most people miss) is the studs which a TV mount bolts in to. Most TV mounts are 16" wide, but you want the mount centered. If you have a telescoping arm on the mount, they almost never sit centered and are offset. This is why what Brad did is great, as it lets you put the mount wherever it needs to go without modifying anything. True they make very good toggle bolts that just grip the sheetrock, buy why not use wood studs if you can? Also, take good photos of every single one so you know what you working with once everything is done I also ran extra conduit (smurf tube, flexible pvc, etc) from each of these to my unfinished basement. IMO all of my "over the fireplace TV's" will never have any boxes connected to them, but ya never know. You can also transfer HDMI signal over cat6 if you really need to (say for security cameras, not a 4k movie...) so some people run 2x cat6 cables everywhere just to future proof. I didn't Plan an "IT rack" space somewhere in your house. Most use an unfinished basement room, the cabinets can be locked etc so that part is up to you. Yes everything is wifi today, but hardwired is always better and more reliable. Depending on the size of your house, most will do a WAP (wireless access point) system instead of a single bulky wifi router that sits on your basement IT rack or another bad spot. Planning a WAP puts your wifi router in the best possible location in your house, or you could do 2 or 3 WAPs to make sure there's no dead zones etc. Anyway, these need cat6 ran (from your rack) to their location (and sometimes 110v outlet so plan hardware now). Same with security cameras. If you want them or to wire for them, that all needs to feed to your IT box Put your IT box on its own circuit. It might not pull a ton of power on it's own, but you don't want a vacuum cleaner tripping a breaker on accident and killing your data signal for the entire house.