Strictly historically, Camel and Dr1 should be tightest turning, Camel more so to the right. DVII could turn about as well as a Camel could to the left. The advantage of the Camel was partly its turn, but also its sheer agility. It could apparently carry out impossible-looking manouevres, thanks to that close-coupled layout. It was, however, damn dangerous for inexperienced pilots.
SE5a and Dolphin (not available in this game, though I'd love to see it) had the advantage of speed but also range and altitude.
For proper historical accuracy, the D.VIII should break up in the sky at least once in a game! (OK, that was the E.V...) It was fast, especially for a rotary-engined aircraft, but not that fast. The Bristol M.1 had the same top speed, even edging it by 1mph, and that was an older design with less power. Rate of climb would be reasonable (trading low weight and low drag for higher wing-loading). Altitude performance with that thick cantilever wing should be good too. Unfortunately, the action in DF seems to take place at low level most of the time so we don't get to explore the differences at altitude.
Hey, Zup - can we make the zeppelin fly at 2,000ft? That should entice people up high for a change.