DESC: LaCrosse production car should do much for Buick's fortunes in the cutthroat family sedan segment. It's a direct replacement for the Regal and its budget-oriented Century twin, but a new engine, a higher-quality interior, a longer equipment list and a reworked suspension should allow it to move uptown in image if not in price. On the outside, the LaCrosse blends traditional Buick styling cues - a softly curved hood and a vertical-slat grille - with current-day trends.