Another simple but effective idea and not that expensive
What you could do also is Buy a second joystick and make that a collective (i got my idea from JasonJ, because he has the same config and my second joystick will arrive on Saturday)
I already have a Extreme 3d pro, but it isn't great for flying with a collective bird (slider is not that accurate, cause it functions alot different then the FSX collective)
So i bought a second Joystick (logitechs attack 3) and i can't wait to try it out... It has one dissadvantage and thats the automatic centering, but perhaps some tweaking could make that dissapear..
Cheers,
TG1984