I've tried to getting used to it but then switched to Maru maru.readme.io
The reason is, it's too much like Rails IMO. Enforcing you to do the Phoenix style of MVC is not what I want. Also, it tries do apply 'good practices', but those aren't mine.
Using microservices and for the view'ish viewing part, I have a good Node.js + React.js setup. Why should I ever go back to templates with enforced 2-way-data-binding?
It took me a little to grasp the internet for alternatives, but I've found Maru, and it also sits on top of Plug like Phoenix. Phoenix plugins can be used with Maru too.
But this is my unique path. I think only a few handful of people do stuff as I do it. Means, Phoenix may suit your needs. Just give it a try. Oh, and it's ultra fast (they measure response times in microseconds).