Andy,
Look for zippered cuffs that are tight when zipped, a flap behind the front zipper to block air through there, and a waist belt that is adjustable. Lots of pockets are good and a snap collar as you described. Riding jackets aren't necessarliy the same jacket you would wear out to the movies. Mine is far to heavy for that. I think I paid 125 at a bike swap meet. Also, just as important is a set of matching leather gauntlet gloves. There you go, 35 years of riding experience and untold numbers of jacket combinations. I took my gloves and jacket to the ground with a broken arm and a wrecked CB750F and still wear them with the scuffs touched up with some shoe polish.