Once you grok Lisp, everything else is easy. You come to realize that the vast majority of what passes for "new technologies" is really just a re-discovery of something that exists (or is easily implemented) in CL. That makes it a lot easier (if a tad frustrating at times) to keep up.
EDIT: CLOS, and generic functions in particular, are a HUGE lever that no other language has co-opted yet.
So much this. (From a soon-to-be geezer who's staring down 40 soon.)
Check out Dylan, Julia, and my old hobby language Magpie.
I highly recommend guile to anyone who wants the battery included nature of common lisp. I know that racket is also a great choice here, I just have little experience with it.