Not all biplane aces flew in WW I. I recently found this interesting site from Sweden, detailing nearly 50 aces from about 7 countries in WW II. The major players were Gloster Gladiators, Fiat CR.32/42s, and the I-15 series.
Naturally, many aces who flew only in the Spanish Civil War also were biplane-mounted.
http://www.dalnet.se/~surfcity/aces.htm
Real Men Fly Biplanes
Barrett