The problem is that your first language has an incredible impact on how you think about programming - the good thing about starting from scratch is that you don’t have any preconceived notion on how things are supposed to be. Learning “those other languages” first can actually erect obstacles to learning languages like Elixir. I’ve already expressed my current preference on “how to learn to program” elsewhere so I’m not going to repeat it here.
Short answer: Give priority to Programming Elixir 1.3 and depending on how committed you are, consider acquiring it via the Starter Kit for Elixir Development (it also applies to “Programming Elixir 1.3”).
Now of all the other languages you listed JavaScript is the next most important one because there is just no getting away from it in web development - no matter how much you may learn to “hate” it in the future (same for NodeJS, not because of its use as a server but because it is such an integral part of the web development tool chain). It is essential that you become competent in it eventually - no matter what your personal opinion on JS in the future will be. But it probably is a good idea to pick up some good habits in Elixir first so that they can rub off on your JS.
Ultimately you should aspire to the JS style that is showcased in JavaScript Allongé, the “Six” Edition to make your JS-experience as pleasant as possible. Focus on ES6/EcmaScript 2015 - not because of classes (
) but because of destructuring, template literals, generators, etc. Probably the best on-line resource to expanding your JS knowledge is the “You don’t know JS” series:
- up & going
- scope and closures
- this & object prototypes
- types & grammar
- async & performance
- ES6 & beyond
See also the [ECMAScript book topic] (ECMAScript book).
I will not name by which language. 
