I guess what you're trying to say is that once you adopt Promises a large portion of your code will have to be tailored to use it.
To which I respond: .. yes, so what? It's better than callbacks. And it's better than some "magic fairydust" that doesn't make it explicit that you're doing something async.
Edit: And the "problem" with async/await and CoffeeScript is that the former is currently available in various JS transpilers but you can't use one of those and CoffeeScript at the same time.
This isn't a necessity, since you can create a function which both returns a Promise and accepts a callback. Most Promise libraries make this easy to support, which makes it easy to introduce Promises into projects that already use callbacks, and vice-versa.