I am not sure if your ship is visiting Puerto Vallarta but we did an excellent Canopy Zipline & ATV Tour and the price was excellent! We didnt book it with the ship though but through a reputable online company. If you are going to Puerto Vallarta, dont miss this tour, its truly the thing to do!;-)
if you are comfortable booking with a local tour operator and you find a reputable one, it is usually much cheaper than booking with the cruise line. There are a few exceptions - there are some tours that you can only book thru the cruise line, and if water travel is involved it is usually a good idea to book thru the cruise line because what if the boat you are on has a mechanical failure or something that causes you to be late for departure? you are out of luck if you are on your own.