Our house came with a screened porch in disrepair, but we loved the idea of a screened in porch, so we kept it with making some changes.

- First, ours too faces west, so it gets hot! Had electrical run to install outdoor rated ceiling fan and while we were at it, electrical on the outside for extra use - Christmas lights,  outdoor equipment.  

- Did I mention it gets hot! So we closed in the top pitch of the roofline that you have there in the example and just kept screens on the bottom so I could install shades easily.  Yes, less open,  but I wanted to stop the sun!

- Also, picked a midrange UV/sunguard screening to cut down on the sun intensity. Not too dark, but enough to cut the sun rays a bit!

- Our porch was already a footer style build (no slab or crawlspace) so we kept it, but put in new river rock protection underneath, took the entire wood floor out and installed Trex composite decking with new screening underneath. 

- We also get a lot if rain and snow, so instead of bottom rails, went with full knee wall on the bottom and actually installed siding (in/out)over the framing for durability - painted so it matches the house cement board/hardie plank. Also the sills are angled down each side to allow water to drain away from the windows. 

Good luck,  we love the extra living space spring to fall, love to entertain guests out there,  work, read, nap, eat, etc. :)

Hard to convert a screened porch to glass at a later date and have ti turn out well inexpensively. Have you checked into using EZE BREEZE Window Units. If you are DIY they will sell you the windows and screen directly.

https://ezebreezestore.com/?gclid=CjwKCAjwiJqWBhBdEiwAtESPaJwzogstGndCEOnSDqMkYD713bs_1xeAWY_24KgsgcuxVd1qoAEdbBoCsPIQAvD_BwE

Not sure if you're expecting to use the existing or not, but you will probably have to redo the entire thing - the foundation of the current deck was likely not designed for the weight of a screened porch. If you already know that, great - you are on your way.

Adding glass later is fine, but you need to buy from a company that will sell you the frames with just the screens with the option to buy the glass later.

As far as TV goes, you place it where it will get the least sun. If your back of house faces south, I would put the TV on the northwest wall of your house. The roof will shade it in the summer. In the winter, you shouldn't get glare on it in the later afternoon.

If it faces west, I would put it on the south side. I would also consider springing for an outdoor TV, which helps with the brightness issues.