I don't think you're missing out on much. Lisp is probably the least interesting of the functional programming languages. I think Haskell has more interesting ideas if your interest is purely from PL research standpoint. For practical purposes, I don't even consider those languages. Their main value for me is the slow cross-pollination and trickling down of ideas (such as lambdas, type inference, algebraic data types, etc) to more practical, mainstream languages.
Lisp languages are not even functional programming languages, they're mostly general purpose. Lisps are interesting for other reasons such as the s-expression syntax being similar to the AST, lists and other data structures as first class entities and so on. Also they are very practical languages. Clojure and Common Lisp are used in real world production systems for example. Missing out on lisp is missing out on a lot of interesting ideas.
