moving on from python
I didn't see you mention SciPy on your list... I tend like R syntax better, but they cover much of the same ground.  SciPy has faster matrix and array structures than the general purpose Python ones.  Mostly places where I have wanted to use Cython, SciPy has been just as easy / fast.  
GNU/Octave is an open/free version of Matlab which might also interest you.
I use python heavily for manipulating data and then packaging it for statistical modeling (R through RPy2). 
Feeling a little restless, I would like to branch out into other languages where 

Faster than python
It's free
There's good books, documentations and tutorials
Very suitable for data manipulation
Lots of libraries for statistical modeling

Any recommendations?