While this is not to be considered an authoritative packing list, here are a few items that we have found handy when backpacking around Ecuador:
Flashlight; clothesline; mosquito net; Swiss Army Knife or Leatherman (but don't forget to put it in your checked luggage!); watch with alarm clock; toilet paper; plastic bags for separating dirty and clean clothes and shoes; needle and thread; biodegradable soap; notebooks and pens/pencils; hat; and poncho. Antibacterial hand gel is less wasteful than wet wipes. Tents and sleeping bags can be easily rented and you will find that camping is often the same price as a budget hostel.