"I am a much better person today than the one you sentenced," Susan McDougal told Judge George Howard Jr. yesterday after he reduced her sentence to time served. "I promise you won't be sorry." But to stay out of prison, McDougal will have to persuade more judges and juries of the same -- or at least convince them of the deterioration of her spinal condition that persuaded Judge Howard to free her on compassionate grounds. The former Clinton Whitewater associate goes to trial in California next month on charges she embezzled $150,000 from the conductor Zubin Mehta when she worked as his bookkeeper from 1989 to 1992. And when she gets through that, there's a second contempt citation from Starr in September for her continued refusal to cooperate with his investigation. McDougal served 18 months for her earlier refusal to cooperate with Starr, and was into the fourth month of a two-year sentence on Whitewater-related felony fraud charges. But while she may have to spend most of her days in court over the coming months, at least now she can choose what to wear there.