I got real burn out with front end, with emberjs, angularjs, and now react. I'm going to just wait this out until ES6 come about and see where that go.
I think in general I moved toward back end with all the big data and data science is going to be at. And now I'm going back to school to become a data science practicioner.
The trick is to have enough experiences and understanding overall concepts. I've done a variety of MVC in different languages and was thrust upon to do frontend and all that jazz. Those experiences will help you solve problem easier and hone your skill set in finding solutions.
I've seen people talking about how full stack is unicorn. I'm a full stack, I'm experienced in many technologies, master of none but a very small subset. I am constantly surprise how I am way more qualified than some of those frontend programmers or architecturers out there.
The deal is just continue to gain experiences on variety and you'll hone your problem solving skill. You might also be under selling yourself too. There are very few engineers out there and there are tons of pretenders. I've worked with two "front end" and a "acting cto" that specialized in architecture. They were anything but the position they claim to be but they sure do have a purrty linkedin profile with tons of people writing good things about them.