Welcome to the forum!
Have you read this page about ventilation? Chickens need way more ventilation than you'd think, and this page gives an excellent explanation about the difference between ventilation and drafts.
https://www.backyardchickens.com/web/viewblog.php?id=1642-VENTILATION
If you get hot weather in the summer, you might think about having that plexiglass window switch out for a hardware cloth one, or maybe have the plexiglass panel as an awning over hardware cloth. Small coops can get unbearably hot inside in the summer without more ventilation than you use for winter, too hot even for chicken occupancy. Most chicken breeds actually handle severe cold much better than they can handle extreme heat because of their down insulation, which they can't take off for summer. If you do have hot summers to contend with, be sure to site your coop someplace that gets as much natural shade as possible.
Another point about siting of the coop: pick a place in your yard that has good drainage and doesn't stay wet or boggy after heavy rains.
Chicken wire isn't predator secure, so if you use it for your run you can't count on it keeping any predators out. For such a small run, it wouldn't be that much of an expense to use hardware cloth (welded wire) and make your chickens safer. If you do use the chicken wire, be sure to lock your chickens up inside the coop every night when predator danger is greatest.
Cutting a pop door (or chicken door) in the floor means that your bedding (whatever you put down on the floor inside the coop, usually pine shavings) is always going to be falling out the hole in the floor unless you build a lip of some kind around the hole to contain it. It'll be much easier to build this before you assemble the coop and put the chickens in and discover this problem.
If I understand your diagram, the run is 3' by 6' right? The usual rule of thumb for stocking density cited here is 4 square feet per bird indoors (coop) plus 10 square feet per bird outdoors (run), but to my mind that's really more of a minimum guideline. By that measure, your run is a bit on the small side for two chickens, but could work if you really plan to free range them most of the time anyway, or if you pick breeds of birds that tolerate confinement well.
Have you thought about how you're going to clean the run? Droppings will build up under there pretty quickly.
The other thing to think about is predators digging under the edge and into the coop. You can prevent this by adding a hardware cloth apron attached to the base of the run and extending out flat on the ground for about 2 feet or so. Predators begin to dig at the edge of the fence, hit the wire, and don't realize they need to back up and start digging at the edge of the skirt.
Edited to add: Now that I look again at your design, I realize this is a tractor, right? Then you won't be cleaning underneath, but moving the tractor every day or so. You can still use a wire apron to deter digging predators, just weight the corners of the apron with bricks or blocks of some sort. That's what I do with our day tractors.
