The value that Parenscript adds here is the same as for programs that run in a web browser: you write your JS in a Lispy way at a higher level of abstraction, mostly because you get the full power of Lisp macros. There are other wins too, but that's the big one. The runtime environment, though, is entirely JS, because PS is a compiler that targets JS.
So I still don't see a difference in intent here between what PS is good for and what you're doing. I don't want to discourage you at all. Just curious about the differentiator.