First time Cruising - Isle of Pines & Nomea

Hi, I am going on the Voyager in about 3 weeks, I have read some reviews and thinking about doing a tour at Isle of Pines and then hop on/off bus at Noumea.

My main question is, how long do you normally get to spend at a port? The tour at Isle of Pines I am looking at starts at 9am and back at 3:30pm...I am just worry whether I will make it (get off the boat by 9am) or will I miss cut off time back on the cruise (back to the boat by 4pm)?

Also, any recommendations for both places?

Thanks heaps

Are you booking your tours on the ship or with the locals?