I do think there may be a problem or two with using a plane radio. First one is, you have no center detent for neutral on the throttle stick. Most ESCs require a full throttle sweep to calibrate, but that won't work if you're technically using the bottom half of the stick throw for brakes and/or reverse. I'm fairly sure you can program a center position, but it would still be weird without having the spring center-return.
But then you say you've done the 4+ channel already?
I'd personally have to lock 2 of the 4 gimbals, it would annoy me even though I fly. A surface stick radio should have only up/down and left/right IMO, but I am that oldschool... still I use a pistol TX and wouldn't go back. I guess I really don't understand your issue with a trigger radio??? Are you lefty?
There may be a little sticker shock here, but here are 2 I found that would be much better suited to your purposes I think-
Futabe 2.4 2Ch
http://www3.towerhobbies.com/cgi-bin...1&I=LXSNN8&P=3
Airtronics 'crawler' radio
http://www.hobbypeople.net/gallery/751726.asp
FWIW...