I've found that all of the things I really like about Racket are simply because it's a Lisp: it would be just as easy in Arc. I bet it'd also be just as easy in other Schemes or Common Lisp.
The primary benefit of Racket over JS is that: Racket represents programs as lists. These lists can have arbitrary stuff put inside them (like actual functions). Racket is highly optimized and executes code very fast. Racket also optimizes common functional-programming patterns, like the "let" macro in Arc.
But that isn't really tied specifically to Racket. As for Racket-specific stuff... I guess the fact it has nice immutable hash tables and boxes built-in? That's about the only nice Racket-specific thing I've found so far.
So I'm not really saying "Racket is awesome", I'm really saying "JS sucks, and I wish I could eval a JS AST rather than a JS string". But yes, it is cool that Racket is a Lisp, and so it makes code compilation easier than non-Lisps.