First, my BIG mistake was it should have been the F3F, not the F2F, and it did see action in China with the Chinese Air Force.
Also, I don't remember how many, but the RAF's greatest Ace of WWII, Marmaduke St. Pattle (of South Africa) shot down a good number of his 50+ victories in the Gladiator. And there were a number of Italian aces who started in the CR32/42 series.
I think the biplanes could give the others a run for their money in a dogfight. While they were slower, they could also turn tighter than the faster monoplanes.
While I'm thinking of it, the Russians had a biplane fighter that saw action in early WWII as well. The Polikarpov I-15/I-15bis. The last version of the I-15 had retractable landing gear. One of the few biplane fighters (along with the Grumman F3F) that did.
Most had fixed undercarriage.
I read where a tactic the Russians used was they would fly the I-15bis with the undercart down until they engaged the enemy, then retract it, giving them less drag, more speed, and generally surprising the other side. I guess it worked for at least the first few encounters.