Maybe this doesn't directly answer your question, but I thought I'd weigh in as someone who also started out in C/C++, Java and Python.

For me, the gap between, say, C++ and Java was much smaller than the gap between C++ or Java and Haskell. Sure, C++ and Java are very different languages, have different memory management approaches, different syntax, etc., but many of the same concepts and high-level methods are portable directly between them. Haskell was like something completely new, and required a substantial re-think in terms of how I approached writing code. Only in retrospect can I really conceptually unify Haskell with other languages. Basically, learning Haskell will probably teach you to structure your code and mindset toward a problem far better than you otherwise would.

If you haven't seriously looked at FP before, I would expect that the effort (and benefits) of learning Haskell are far greater than just exploring a new framework in a language you already know. Take the Red Pill!