Both hex and ascii85 will align at 1024 byte boundaries, base64 will align at 1024*3 bytes, so you'll end up with a symbol stream something like this:

symbol_1, symbol_2, symbol_3, ptr_to_1, ptr_to_2,...

ascii85 performs better than hex simply because it's dictionary is shorter.

If you compress something with a bit more structure, like "Hamlet", you'll get this:

    >>> import urllib.request,zlib,codecs,base64
    >>> hamlet = urllib.request.urlopen("http://www.gutenberg.org/cache/epub/2265/pg2265.txt").read()
    >>> len(codecs.encode(hamlet, 'base64'))
    248577
    >>> len(codecs.encode(hamlet, 'hex'))
    368018
    >>> len(base64.a85encode(hamlet))
    230012
    >>> len(zlib.compress(codecs.encode(hamlet, 'base64')))
    102788
    >>> len(zlib.compress(codecs.encode(hamlet, 'hex')))
    88827
    >>> len(zlib.compress(base64.a85encode(hamlet)))
    121364