The thing about both Lisp and Smalltalk that keeps making me feel alienated is that their power seems much weaker beyond their kingdom. The outside world does not have an object browser, nor is it made of s-expressions.

Tcl occupies a very nice place in this regard: its homoiconicity and symmetry (and late binding) come from text. The outside world, to a very close approximation, is also made of text. Subprocesses, sockets, FFI, files and user interaction just feel more native - in the image-oriented languages, I always find myself fighting the ambassador who imperfectly represents these things in forms the kingdom understands.

Just a feeling. They're all wonderful languages, and this article speaks well to some of the "why".