Very good reading to be honest.

I would have some questions:

1. You say linea alba is important for alignment of the body. But this means alignment in the frontal plane (looking from the front), what about alignment in the sagittal plane (looking from the side) ? 
2. These are the main muscles for movement, but no matter how perfect they function, you cannot have natural movement without the stabilisers muscles working good as well.
3. But I presume you are saying that if this muscles work correctly, every other muscles will function correctly as well. I cannot say you are wrong, I don't know the answer, but from my past experience I had issues with the traversus abdominis which is very important for lumbar stability. I could improve the rectus abdominis (superficial muscle) as much as I want, this didn't fix the problem for my deeper muscle, until I started concentrated on it.
4. For some reason whenever I read about pelvic floor (in this article) I would always think about the traversus abdominis. For movement I feel this is much more important. But again, just my opinion, I don't have much information about the pelvic floor muscles.

Again, it was a nice reading. I rarely found someone opinions to be so intelligent when it comes to the human body.