You might be better off flying via SCL. I was in Easter Island last year and had flown from AEP - SCL - IPC. Clearing immigration and customs in SCL was easy and the airport is a comfortable airport to transit through. On arrival at IPC I'd met some rather tired, worn out travellers at the hotel where I was staying who had an ordeal clearing immigration and customs at IPC as the airport was small and there weren't enough immigration officials to process a plane load of passengers. One of them said something to the effect of "it was pitch dark when we arrived, immigration and customs took nearly two hours...". Definitely not something I would want to have to deal with after an overnight flight.