As for posture imbalances notice the posuture of Sanchin or Ten Sho KATA or the Qi Gong exercises the body structure is aligned and rooted.
Right, I agree with Neko on this.
Further, from what I understand, any correction in 'muscle imbalances', is a direct result of maintaining this alignment and building the fascial connections (or 'body connection' as some imaist's call it).
Gavin actually recently posted a nice article about this often overlooked structure of the body here:
"Seek not to follow in the footsteps of the men of old; seek what they sought."