"I find the Aikikai stance uncentred - not making a detrimental statement before you all jump down my throat"
Heh. Before I started aikikai, I was with a branch of Ki Society... the stance applied was the so called 'aikikai stance'.
I would have a hard time telling my sensei's then that they are uncentered and move like a turtle.
I guess it all boils down to which is most suitable for you and what you've been practising all this while with.
From what I understand, different schools of Ken teach different stances... from the width, through the feet positioning.