Hmmm might have to give corn flour a try.
I have found the rice flour helps add a level of crunch to the crust that wheat flour just can't match. Straight rice flour produces a crust that is way too thin for fried chicken, but a mix seems to give a great mix of body and crunch. Got the idea of using rice flour from a Vietnamese version of fried chicken.
Another question for you, how do you like your oil level? I notice in the pics that you are using a fairly shallow fry. I have started using a little higher level of oil in the pan when I fry. Still not quite half way up the chicken, but a little higher then what you have there. Have you tried a higher level?
Sorry for all the questions. I just love talking to people about their fried chicken. Always interesting to see what other people are doing