ORLANDO - Toyota has improved its Prius gasoline-electric hybrid hatchback by a striking amount. The new car is a little bigger outside, more powerful, more fuel efficient, more luxurious, more refined. Toyota did all that for the last redo and delivered the then-new 2004 model at no increase in price. This time, no such price promise. "The sweet spot for us with this car is still $24,000, $25,000," says Ed La Rocque, small-car marketing manager for Toyota Motor Sales USA. He hinted that a relatively basic model on hand for testing here would be priced about that much. Toyota Prius: More posh and more power