I'm currently learning Common Lisp. After I wrote my first real program with it (not a tutorial), I knew I made the right choice. After hours getting everything to work, when all was said and done, all that was left was this tiny, succinct thing. Was this really everything I was trying to do? Had the answer really been that simple? And I thought to myself, this is what programming is supposed to be, not a bunch of spaghetti code brute forcing one's self through the program, but the search for something concise and beautiful that says something about the problem and solution.

There seems to be a certain personality associated with lisp programmers, which emanates when they speak about the language. So logically I was pretty confident in my choice from day 0. However it wasn't until I actually made a program with it that I was emotionally confident and content with the choice.

In conclusion, I recommend you build a program with Haskell, Lisp, and/or an idea from the dragon book. That experience may give you the best idea of what path will be the most rewarding.