Hi Beth, thank you for taking the time to answer and for the photos. The biggest thing I dislike about porcelain tiles are the rectified edges that have a super straight edging. My current tiles actually have non-rectified edges which make them look a lot more like natural stone. It’s very hard to find non-rectified porcelain tile these days! I really don’t care for the uniformity of the square tiles with perfectly straight edges - I like a softer, natural look. The last photo you posted -the chevron pattern - is very interesting and I will take that to one of my local tile companies to see if I can find something similar because I could really dig that! Photo of my current tile:

You could many different things with an opening that size such as putting in operating windows or doors, put a wall in below with shorter windows, ect. Depends on what you want and how it would tie in with exterior. You could call a commercial glazer and see if they can do just the glass if that is all you want. I would want a triple paned, appropriate low-E glass pack with a warm edge spacer . Keep in mind your glass will look different than your other windows if they don’t have Low-e. Being as your climate can get pretty cold , and. You’re already at 32 degrees I don’t think I would go with an aluminum framed window and you’re building code might not even allow it. Aluminum is much more prone to condensation than other typical frame materials.

Sounds like a better quality build with the larger home. Cheaper builds will not have individual room returns. By negating the return in the room it is much harder to provide that room with 'better' comfort. In a room that has no return ( a place for air to leave the room) will force air out thru cracks and crevices. The room gets blown up like a balloon with the door closed. Remember air takes the path of least resistance. This probably won't seem that detrimental to you as the consequences vary. It falls under the premise of building science and what occurs to building pressure under certain conditions when the HVAC system is running. In some cases the home without the return ducting to each room can undergo areas of the home under negative air pressure. The premise is that air added to a room takes up space that is occupied by air already there, that air has to go somewhere. Hard to comprehend, because this is invisible to the human eye. If the home without the air return to each individual room just left the door open to the room in question there is no problem that way because air has a place to escape the room. Other options are what is called 'jumper ducts' or 'poor man's return' -- these are just merely a duct (typically over head) with a grill attached, no filter as the air escapes the room to an area outside the room to another duct with grill over it -- usually these are joined by other jumper ducts led to the area near a filtered return. The filtered return has a draw to it when the HVAC system turns on, by having the jumper duct / poor man's return ducting near by this relieves the air pressure of the HVAC system when the system turns on. It's all about reducing 'pressure' and creating a more comfortable home. This pressure is invisible. A home with a single return - depending on the size of the system can have an effect like that of a wind tunnel. Many times these single filter returns are placed down a hall way. Standing there with the system on you can feel the rush of air being pulled back. That is what I mean by 'pressure'. Pressure causes less comfort, more wear and tear, higher electric bills. These are all gradual things. Over time they all add up. If you're in a more moderate climate not so cold and not so hot doing anything about it may not prove to be that big of a deal.

Cool tile! We have this size on our floors and no issues. It’s been there for 3 years. We are having the same guys install 48” x 48” on our bathroom floor and walls in a few weeks. They are very meticulous and have experience with all kinds of tile, including larger format ones. We did a lot of research before calling for quotes. When deciding on the installer, we asked for references and asked them questions on how they planned to install, what material they were using etc. That helped us get a good installer. Best of luck with your project!