Thanks to everyone for weighing in with such thoughtful responses. It's so interesting that you all like the navy coat the best. I will admit it's my favorite, too. It would probably be a replacement for the green coat, though, or it would simply be a duplication of that length. (Almost, anyway; my green coat isn't quite as long.) The one drawback for me is that it doesn't have a hood, and I find myself using hoods a lot.
On the long coats, there is some difference of opinion here, and my own thoughts are that I prefer the single-breasted look as well as the color of the single-breasted one. The vintage khaki seems slightly yellow for me IRL, but it's not bad. It's just not a dynamite color for me. On the other hand, the single-breasted style, with the inner zip part and the strings hanging off the hood, is a little more sporty looking to me. I like the elegance of the double-breasted one.
I was despairing that maybe I just don't wear long coats that well, because I so prefer the knee-length. But several of you have given me hope that I can pull it off with the right style.
kiwigal, Sterling, and Suz, I think I'm going to have to keep looking for a long coat, and I like your suggestions of a different style.
Joy, of course your comments are helpful! They support the conclusion I haven't yet found my long coat.
Staysfit, sounds like the single-breasted long one is an "almost" for me, too. I'm encouraged that you were drawn to it as well.
Jackie, great thought process--I like your logic.
kellygirl, thanks--I appreciate your comments on my existing ones. The black one is quite old, but I started wearing it a bit more again last year.
Angie, I did bring home the one you showed. I loved it on me in the store. Then I ordered this second one to compare, and I liked it better, so I didn't show the NAS one here. I can photograph it later so others can see it, though. I liked the slightly longer length and the fabric of the second one; it's more subdued for sure, and that's probably part of the draw for me. It also has a quilted removable lining with the cutest Burberry-esque plaid binding.