I got the impression that Hy is stagnating. They removed 'let' in the recent releases (it's hard to imagine Lisp without 'let'). Also there is no support for async, which is pretty important for modern Python IMO.

Oh my, they removed 'cons' :(

    hy 0.11.1 using CPython(default) 3.5.3 on Linux
    => (cons 1 '(2 3))
    (1 2 3)


    hy 0.15.0 using CPython(default) 2.7.13 on Linux
    => (cons 1 '(2 3))
    Traceback (most recent call last):
      File "/usr/local/lib/python2.7/dist-packages/hy/importer.py", line 199, in hy_eval
        return eval(ast_compile(expr, "<eval>", "eval"), namespace)
      File "<eval>", line 1, in <module>
    NameError: name 'cons' is not defined