Sounds pretty beast. Turtling may be a bit OP and wave attack sounds an awful lot like Imperialist but good ideas overall. Ultimate Besieger/Blockade Builder (?) does sound rather weak though. Maybe you could put make the strategy's attributes live up to its epic name and get extra attack for when they attack cities.
Oh and this should be posted in this sticky:
http://afterwind.com/forum/topic.php?topic_id=273. Quick, post it there before the mods delete this!