Having worked with several functional programming languages, my personal experience is that Clojure seems to lean more towards the productive end of the spectrum than the pure end. There is a definite learning curve coming from JavaScript, but (as someone who currently writes more JavaScript than ClojureScript), I still find that the ClojureScript that I write ends up being simpler will a smaller code footprint than a similar JS solution.

Clojure(Script) is not for everybody, but I love it because it is very natural for me to use, and it seems to fit the way that I think better than most OO languages that encourage top-down design. I agree that security, performance and correctness are good end goals, but they are not the only goals (another one that comes to mind is maintainability), and I have found Clojure to be a good means to reach those goals.