Have you tried Googling "topiary trimming guide" or another similar search phrase? You might run across what you are looking for that way.

You can put the TV over the fireplace, not the best situation but the way the room lays out it is the only logical place to put it. If you could you should add one additional layer on your mantel that could extend it out another 4" to deflect the radiant coming from the fireplace. I would also mount it on a slimline mounting bracket and have the bottom of the TV no further than 4" above the mantle. Ideally you want the TV to be in as straight a line as possible with your eyes. You don't want to look up too high at the TV, it's like being at a sports bar. Also if you can snake up the power and the HDMI from the cable there is a box they make that has both in one so it makes for a very clean installation.

I would move the two chairs against the wall with the table between for a "side" seating area... which can still see the t.v. (needs some baskets or something under that table... a trunk maybe...to bulk it up). Then make an L shape with the other couch/loveseat that you have. You also have great storage along the tv wall but it's kind of bland... punch it up with a color along the back of the bookcases or a funky wallpaper. Drapes for a punch of color with some other accessories and you'll have a gorgeous room. It also looks like you have an ottoman.... put a tray on top and use it as a coffe table for a while.

Try the TV where the sofa is now and float the sofa perpendicular to the fireplace where you currently have the big chair. Perhaps the big chair can then go where the TV was for a quiet spot for one. Or even better, pull the loveseat off the wall and put the big chair to its left flanking the fireplace.