I joke with my buddies that our short grass strip is like operating from an aircraft carrier. Things that helped my jets take off are Power - as much as you can fit in there. Trailing link oleos, make sure your wheels spin as freely as a skateboard wheel. Also I run full flap on takeoff, see if you can extend your nosewheel so the bird has a slight nose up attitude on takeoff. Having a rear biased CG point helps as does extra travel on your elevator just for takeoff, you can change out the rates then when you are in the air for smoother flying.