Taxis/Beach in Majorca

Hello - We are a family of 5 and I think we have decided to spend our day in Majorca at a beach, rather than another tour. Am I correct that Taxis are very easy to find at the port? My concern is that Taxis only hold 4 passengers so do I need to reserve a taxi or do they have minivan taxis at the port also?

Any anyone have strong opinions on Illetas vs. Palma Nova? We just need a beach with bathrooms, and a place to order some drinks and snacks.

How easy are taxis to get back to the port? I know in the Caribbean we would often make an arrangement with the taxi driver to be back at a certain time.

Thank you for your help!

In terms of services I'd say Palmanova is better. They have public bathrooms, but maybe it's always best to go to a clean bar and use the bathrooms there. http://www.visitcalvia.com/

No help on Taxis, in some other touristic parts of the island they have many vans, but don't know if you can request for them in advance or you just wait for one to arrive. These is the taxi's union: http://www.radiotaxicalvia.es/