From what I've read here in forums is that the D8 is actually the same size as others,it just appears smaller because it has only one top wing making it harder to aquire in your cross hairs, this also reflects it's true identity. The only "small" plane on the German side is the mono wing Fokker and then you have the Airco, small and it's allied.(see Rat tat tats thread the size of the d8 is ridiculous").
Taking away the option to choose sides? Not sure I understand your reasoning. How would I join my squad, say, in a battle if I couldn't choose my plane allied or German?
I've earned a lot and spent $ on planes, It would not be cool if I could not choose to fly one of them when I wanted too or needed too.
Too many cons, I like to be optimistic, I'm sure more pilots will pick up the new top allied planes as they earn back the coin they spent on the new German ones that's my plan anyways, and I think most would agree that you can't have one top German plane without having one top Allied plane.