[The HACK]

I'm about as serious as I ever am on teh intarweb. I've seen racers alter their brake pedals by welding a block of iron or bolting on a thick aluminum extension to artificially "raise" the brake pedal a few inches. Not the most elegant solution but it works. Don't be afraid to try it.

As far as blipping at the beginning of the brake zone and over-revving it...If you are indeed bouncing off of the limiter as you blip and downshift then you are over blipping your throttle anyway. The point of heel and toe downshift is to match the amount of deceleration to the next lower numerical gear's multiplication, therefore if you were to execute the blip and downshift at the beginning of the braking zone, you wouldn't have to blip as hard and you will only be in your first 1/3rd of your brake pedal travel making modulating the throttle easier. The typical mistakes I see when learning how to heel and toe is waiting until the end of braking zone to do the downshift since by then your RPM would have dropped too much and your foot already buried on the brakes to effectively blip the throttle, and it requires a much larger "blip" to accomplish the increase in RPM needed to account for the large discrepancy in road speed/deceleration and gear multiplication.

That, and by completing your downshifts earlier it gives you an opportunity to concentrate on the end of braking, the part where you have to taper off and transition to turn-in as smoothly as possible in order to apply throttle as early as possible, in order to go fast.

This is the sort of thing that having a professional coach or an instructor willing to sit in the passenger seat that EVERY driver will benefit from. I never pass up the opportunity to take an instructor buddy out to critique my driving nor do I pass up the opportunity to ride with another instructor to learn what they're doing plus offer them some pointers of my own.

And I would suggest watching some pro in-car videos and listen to the engine note at Laguna Seca. I'll venture to guess that they almost always start their downshifts right after they start their braking, even for the hairpin. Not saying that I believe we are all skilled enough to do what they do, but as far as "best practices" for track driving is concerned, it never hurts to see what the people who gets paid to do what they do best, do.