Acapulco is amazing and one of my favorite cities in the world!! I love Mexico in general, but my heart will always be in Acapulco.
Cliff diving is way too touristy for me. The Cross or Chapel of Peace is indeed spectacular with views you can't imagine. My mother's ashes are there Beryl...the family flew down to intern them this year. My parents, like myself, have been in love with the city for decades, which is why she chose her final resting place at The Cross.
The Acapulco Princess offers tons of activity and amenities. The main drag - Costera Miguel Alemán - is a wonderful place for walking around and sightseeing. Taxi's are CHEAP - the ship will be far far away from everything. Grab a taxi and tell them to let you off at Carlos n Charlies...middle of everything...maybe a $5 cab ride. The nightclubs can't be beat. Sadly, most ships leave before the city 'wakes up'. If you are lucky enough to ever be there overnight....you MUST have dinner at Coyuca 22...that's the address. There are no words and I wouldn't want to spoil your shock when you enter. CANNOT IMPRESS ENOUGH TO ANYONE - YOU CANNOT MISS COYUCA 22. Only open during "season" - Nov - Feb
http://www.fredsphoto.on.ca/aca07_Coyuca22.htm
I've been to Acapulco many many times, and would go anytime in a heartbeat. Here's some more ideas. I find the people who dislike Acapulco don't embrace the culture...they'd be happier in Vegas. And if you ARE up to making a night of it, after dinner at Coyuca - hit Baby O's - the BEST nightclub in town..opens (like most) at 11pm. You'll LOVE it.
http://www.fredsphoto.on.ca/aca_sights.htm