I didn't notice the appendices in the draft. This may help, but the version I reviewed has a brief review of Linear Algebra and Statistics in Chapter 1. The language is written in a way that assumes mathematical familiarity. Putting this level of 'sophistication' in a "practitioners" book early on may turn off a certain demographic of readers. I say 'sophistication' because it's relative to the reader-- to someone with a math degree this section isn't sophisticated (in fact they'd find it completely trivial) and can be skipped. To a software engineer that hasn't taken a Linear Algebra/Statistics class in 10+ years this may appear too much for them. You risk losing the readers entirely or having them skip those sections. Again, this review is not friendly for the beginner and the 'practitioner' title is misleading here.
In my opinion it wouldn't be too difficult or much effort to define what these mathematical objects are and show basic examples with basic computations to solidify the concepts. The notion of gradient descendent & derivates (or partial derivatives) isn't that difficult to understand and could be easily explained in a page or less.
For example when you discuss the Outer Product:
"This is known as the “tensor product” of two input vectors. We take each element of a column vector and multiply it by all of the elements in a row vector creating a new row in the resultant matrix."
It would be nice for the beginner to see an example of this and as stated it wouldn't take much space in the book to provide one. I think these sort of things would differentiate your book from others. If you made it more friendly more 'practitioners' would be willing to read/use it end-to-end.