Quick sketch of RSVP.Hash wrapper

gistfile1.js

model: function (params) {
  
  var FetchPromise = Ember.RSVP.Promise(function (resolve, reject) {
    Ember.RSVP.hash({
      dinosaurs: App.Dinosaur.find(),
      ninjas: App.Ninja.find()
    })
    .then(function (objects) {
      resolve(objects);
    })
    .fail(function (errors) {
      //handle errors here and call resolve on YOUR terms.
      //Perhaps you could recall FetchPromise
      //Perhaps you could just resolve with empty arrays.
    })
  })
  
  return FetchPromise;
  
}