We are looking forward to our trip in September too, and are particularly excited about WL for many of the reasons you listed. Since September is usually a lower crowd time, we have had good luck in the past getting upgraded room locations while booking Standard View. Like others have said, booking Standard gets you Standard view or better, and we have wound up in the "or better" side of it during three previous WL stays getting Courtyard View once and Woods View twice. This was without making any special request other than standard room location requests in our reservation.
This year the construction does add quite a twist, because the only currently bookable categories are Standard and Courtyard View. In my opinion, since there are still a large number of formerly Woods View rooms still in use in the North wing, I think it is highly likely for someone to wind up anywhere on the North side of the North wing with a Standard view reservation. You will be able to see construction along the shoreline below your balcony, and there are fewer trees due to the construction, but your balcony will likely face MK and you may be able to see fireworks from higher floors. Of course if you really want courtyard view then booking that makes sense, because that is the only way to guarantee you will have a courtyard view room, and many people have done so to minimize construction views from their rooms.
There's always that possibility, and I have read stories of people getting larger rooms than they booked, but since there aren't the different bookable views on the DVC side I don't think there is as much opportunity to get "upgraded" to a better view since they are all considered the same. That's ok though, you'll still be at WL and any room there is great to get to stay in.
