Based on the leaves on the ground and a guess about your climate: yes, I'd install a storm door. :) They help with heat loss, of course, but they also protect the door and hardware from the elements. My grandparents' home does *not* have a storm door because they didn't want to cover a beautiful new paint job, with the result that we've had to repaint it every five years or so. :( In climates with sleet/hail/snow (which usually also have some intense spring storms!), storm doors usually don't detract from the appearance of a house because everyone expects them to be there! In my neighborhood, house numbers are spray-painted on walkways: definitely not the best look ever, but very important for emergency services, and let's face it, most of us spend very little time staring at the front of our house. Is there room to put some decorative numbers on the flat portion of the overhang? They might not be large enough for emergency response, but they would be very visible from the street for guests/UPS/etc., but leave clean lines around your doorway. The front of your house looks beautiful, BTW: wonderful work!

One mistake that you made was getting the builders carpenter involved. Should have gone back to the original maker of the door, first. Our newly installed manufactured door is unstained for the next few weeks. It is already swelling with cold temperatures, rain and snow. Needs to be stained ASAP. However, I am worried that if we stain it now, it would stay swelled and not shrink back down. Ours came with the wrong color of threshold and hardware (hinges and handle.) Black instead of ORB. Not sure who's fault that is, but it is what it is. I guess it was a blessing. (See below) We also had two sets of French doors, as well as a single installed. While the handles are black, the hinges on the doubles are bronze (thankfully, these are outswing doors.) On the single (which is an inswing), the hardware is all black. The doors are in the same room. LOL We would love to see your new door...cracks and all!

I can't believe I'd say this, but stylewise I don't think your existing doors are quite perfect. One is fine, but it doesn't work as well as a double door. I think the doors you are thinking of would be a fabulous upgrade appearance-wise. You could do a sidelight but I think the double door works nicely, and you'd get plenty of extra light with the new style. If you keep the doors, which are certainly nice enough, consider a brighter color. The black is elegant but if you think it feels too dark, an easy, traditional choice would be red. (The particular shade might not be so easy!) I guess paint color goes for new or repainting, but the new ones won't be as dark due to all the glass so I'd keep them black. I think the fake wood doors look pretty bad when "stained". If your climate doesn't allow for actual wood, don't stain it please! Before painting, be sure to get LARGE samples painted on posterboard or something to see if it looks right.

If you want a bigger window then you need a bigger header so are you willing to rip out the wall and add the larger header. IMO keep the header the same and just replace the bay with a picture window. I see not reason to make it lower but that can be done with some work and mess. I do think you should draw out what you are thinking to see the look I llike windows to be the same ideally or very similar in height and style. or else the exterior gets very busy looking New front door is needed for sure as the one you have in no way works with the house and I happen to like double doors at entries just for the practical reason it is easier to move stuff in and out a simple double door with glass would be my choice. As for color of siding I think you need to wait until all the windows are in and the new door chosen. For sure no grids in the windows and you need to decide what style of exterior you want. IMO you could go cottage ot MCM so take some time to think about the style since the windows will need to reflect that IMO.Your fence idea book says contempory or MCM so is that the road you are travelling. If so then all the windows IMO should also be the same style and the same height off the floor along the front of the house and it would be good to see the whole house.