I've had this issue before (still do from time to time), what I do to fix this is I take off at an angle, something that took some practice getting use to, once you catch the wave you'll already be heading the direction you need to go, then, try and stay closer to the top of the wave to maximize the waves enegry, pump to increase speed and when you think you might have enough momentum, drop down for a little turn up the face, but in small waves there is only so much you can do.
Also, as some have mentioned, getting more weight on the back foot will lift the nose out of the water some so you can pivot, start that motion by looking at where you want to be and transfer the turning motion from your shoulders, to your waist, all the way to your feet, in one fluid motion.
I'm 6'5 225 lbs and I don't ride anything longer than a 6'8 Al Merrick FlyerII. My gun during anything over 10ft. is a 7'0 Bushman. Your prolly trying to do too much. Know your skill limit. Perfect you're longer carves try to do everything smooth. All else fails.......go buy a longboard.