Pusher props for WW I fighters

Watching the Ultralight tow planes at the Finger Lakes Aerosport Park
(http://www.fingerlakesaerosportpark.com/)
Labor Day Week fly-in, it occurred to me that WWI fighters could have
solved their gun aim/synchronization problems easily by adopting a
pusher prop configuration. Wondering why this solution was never
adopted, I realized:
1) The engine in front provides a modicum of protection for the pilot.
But surely, an engine behind would avoid the more dangerous tail
attack.
2) Cooling of the engine might be more difficult--but now the castor
oil is blown away from the pilot, not into his face.
3) Strength of the fuselage, arranged for a pushed configuration might
be less certain. OTOH, several of the original jennys were pushers.

Picture of a pusher prop ultralight:
http://www.fingerlakesaerosportpark....Rhet-plane.jpg

Any thoughts about this tradeoff?

John Bailey
http://home.rochester.rr.com/jbxroads/mailto.html