Put your hands out on the hoods and then the steering won't be so squirrely. I have interruptor brake levers on my bike and I love them. But when I'm steering through tricky territory, I use the widest part of the bars. After a while you'll get to where you can go through anything at any speed with your hands on the top, but you have to practice.
eta: and maybe your levers are too close to the stem--even so you can still put your hands as far out as possible on the top and that will help, too.
Karen