If you're comparing the rear brake's stopping power to the front there is a big problem. The front brake always does the majority of the braking and it should be much more powerful. Campy even goes a step further and deliberately uses a brake with less power on the rear. That makes it quite difficult to lock up a rear tire, but not impossible. That's better than a touchy brake that's easily locked up, IMO. I've had some folks strongly disagree and feel that a light touch is preferable. All I can say to that is you have no control over a bike if either of the wheels stops turning and you can rub through the entire tread thickness in a matter of seconds if a tire does lock up.

You may notice that virtually every vehicle on the road has more powerful brakes on the front than the rear.

Measuring the distance from the pivot to the brake cable attachment point does not tell the whole story either about a brake lever. As an example, Campy completely redesigned their brake levers for '09. The pivot to cable attachment distance increased from 19 to 22mm, but the length of the lever was also increased. Measuring from the center of the curved area where your fingers are supposed to go, the old levers are shown (by Campy) to have a length of 76mm while the new ones are 88mm. Both have the same 4/1 ratio that Campy also claims is "the same as the competition". It must be common for road calipers to require approximately a 4/1 leverage ratio.