Using a Lisp-like language is great for creating a new language because of the S-expressions that Lisp depends on.
S-expressions are very compact and are easy to parse. There was actually some support for using S-expressions over XML and JSON as a serialization language.[1]
Ron Rivest even proposed S-expressions as a standard.[2]
I still prefer JSON over them though. As the old joke goes, LISP stands for "Lots of Irritating Silly Parentheses."