> coffeescript/typescript feels more "isomorphic" to Javascript than client/server js libraries.
What do you mean?
I use exactly the same shape (iso-morph) of JS business logic code in client and server and most libraries work out of the box in both environments (unless unable to, such as raw TCP/UDP connections from the browser).
"Isomorphic Javascript" is a bad choice of word because coffeescript/typescript feels more "isomorphic" to Javascript than client/server js libraries.