I'm in a similar position as you. I've been working on a couple of projects for the last 5 months or so. I've been pretty focused on JavaScript so I decided to develop my projects using HTML/CSS/JavaScript to strengthen my grasp of these core languages.
I want to get back to Python and learn Python 3.x in the new year. At the same time, I was advised to stick with one language and become really good at it (I sometimes have a tendency to bounce around a little) so I've been learning JavaScript on the client side as well as on the back-end (using Node, Ember, React).
As it happens, I'm working on two bigger projects and a couple smaller ones. I decided to build all of them in these three languages. It's a great way to learn more, and put what I've learned into practice.
My suggestion is to use the languages you've learned and do as much as you can with those languages. Obviously if there are languages better suited for your project, use that.
That said, I tend towards following the slightly harder route because I really want to nail down the fundamentals.