Close, but if I had to pick the most significant mid-late war fighters, I'd say:
Albatros DIII & DV
SE5A
Spad VII & XIII
Nieuport 17&28
Perkies would have to go to these:
Sopwith Dolphin and Snipe
Fokker DVIII
Siemens-Schuckert D IV
Junkers CL1
It'd be good to also see:
Nieuport 11 and 28
Sopwith Pup, 1 1/2 Strutter, Triplane
Hanriot H.D.1
Pfalz DIII
R.E. 8
Hanover CLIII
Halberstadt CL Series
Rumpler C Series
Siemens-Schuckert D. III
Bombers:
Gotha G. 5
Handley-Page 0/400
That's get us a good late-war set, with more added later for early war (though, arguably, the Nieuport Bebe is a little out of place here).
Oh, screw it. They should just add 'em all - and ALL the WWII birds, too - every single flocking one of 'em.