Let me add votes for the Pfalz D.IIIa, Sopwith Triplane, and Bristol Scout. 1/4-scale or even 1/3-scale would be fine.
I'm also a bit surprised that nobody besides Mick Reeves kits large-scale Sopwith Camels. You would think that it would be more available, given the popularity (notoriety?) of the type.
Dean in Omaha