First of all, Cillai-Kerena, thanks for posting. It's good to have a bit of a chat: far better than mailing out into the ether! Shame you couldn't come into the studio for tea. I guess you'll just have to brew up at home and watch the webcams as we drink ours!
I'm certainly not going to try and defend my point, because I agree that current fashion is quite conservative when compared with other fields (although art and music are equally constrained by commerce I'm sure you'll agree). With designers like Olivier Theyskens or Alber Elbaz, the incremental development of their aesthetic is very, very slow, yes. However, I don't think it is an intrinsic part of good fashion design to bring about radical change twice a year (how many artists have good ideas that often, for instance?).
There is a place for the conceptual designers like Rei Kawakubo as much as there is one for those devoted to consistently elegant dress like Alber Elbaz. I can't see what value there is in setting them up against each other; they adhere to completely different methodologies and appeal to totally different markets. Also, I would reserve judgement until you get a chance to see the Lanvin dresses on the round: side-on, their drapy, billowing backs were as much fun to watch as Union Jacks wrapped around the Comme des Garcons models.
The question of using historical references is another arguement. I think with Balenciaga, the brilliance is in how they play it politically. As you say, the margin for true innovation in contemporary fashion is extremely narrow. It's what you do with that slim space that counts. Especially when most of the key brands are owned by major conglomorates and have the CEO breathing down their necks to make the collections more commercially successful. Fashion, after all, is as much about business as it is about artistry.