Yes, you can leave early but you have to make arrangements with the front desk so the driver of the boat will be there. Add in a little extra time to make sure you will not incur any problems.
The cable car takes around 2 or 3 people and it is auto. The room that we stayed in did not need the trolley car.
Hope this helps, PS
You can email the hotel and ask them to arrange a taxi from the airport. I paid USD70 in January 2018. The driver had a sign with my name on it as you exit the airport.
There is a water taxi that will take you from the dock across the bay to the resort. There is no charge. If you choose to rent a car, you would park it somewhere near the dock. I did not rent a car so I can’t answer exactly where. It would be a short walk. The car does not come across the bay with you. The water taxi runs back and forth all day.
Other water taxis go to other parts of the bay. I did not use any of these and I do believe there is a cost. They would go to other restaurants.