For Clojure, I know there has been talk about this. Clojure allows you to insert Type Hints, which allows Clojure to remove reflection in certain cases, which improves both runtime and compile speed. Typed Clojure should be able to insert Type Hints automagically for you since you provide type information anyway, although it doesn't do that today.

For ClojureScript there really isn't any performance optimization to be done, as far as I know. asm.js doesn't really help out high-level functional languages like ClojureScript.