There's not much on the head you can dremel, but maybe the ports on the cylinder, though there's a lot of science and a bit of black magic to getting it right. It's more than just a matter of opening them up for more flow. There's crank rotation degrees, pulse waves, etc etc, I don't even know what that stuff means really!
That's an '06? Wow, same as mine. I'm always amazed how such a relatively new machine can be so completely beat to hell in such a short timeframe. Some people must be really abusive!
I've never owned the older Blasters with the cable brakes, but I know the brakes on my '06 are really strong. It's made me pass up a few good deals on older machines. I just don't want to deal with the hassle of converting.
G/L with the rebuild B)