Not to be a language weenie, but let me recommend Ruby over Python. It has its advantages and disadvantages, like any language, but as a connoisseur of programming language there is one primary thing I expect you to prefer in Ruby over Python: closures. Python supports closures, but only on a single line. Ruby has arbitrary block closures. I think you will also find similarly appealing semantic details, but since I don't know what, specifically, you are calling nifty, I'm not entirely sure.
Well, I am a language weenie. I've looked at over 100 in the last 20 years. I think I've covered all the different areas including OO (Eiffel, Java, Python), Lisps (Common Lisp, Scheme) and functional (Scheme, OCaml and Haskell).
I recommend learning Haskell. It is different from, and in my opinion, superior to anything else out there now. It has a mathematical elegance to it no other language can match.