At home, things are shifting. My partner went back to college as a mature student three years ago. It was a decision that felt both bold and slightly unsettling at the time. Last week, he graduated. The finish line has reared its head, and with that comes the inevitable question of “what next?” Puerto Vallarta and Manzanillo (pictured here) are both popular destinations on Mexico’s Pacific Coast, but much separates them in terms of desirability…