Silat, I never even thought about that, but it would be possible. You could use the up/down axis for throttle and the left/right axis for RPMs. Or you could use up/down for one engine and left/right for the other. I haven't done much programming for the CH USB suite, and would have to figure out the right way to toggle the engines without the main throttle overriding the mini stick.
Sounds like something to work on while I'm stuck in a hotel room this week.