The answer probably depends on the nature of the books you want to create and if you can work with template based page layouts.
In my person opinion, I believe the design of the book module has been flawed from its inception. Basically, it is template driven. I cannot place an image or a text block on a page without using a template. I can fine tune some aspects by increasing the padding (add space to left right, top, bottom margins of a text or image box). This is a fudge. Adobe should be embarrassed by this, but multiple releases later this major gap still exists.
I would really like to be able to use the Lightroom book module, because the potential for efficiency of workflow is so massive (ie no interim files, images sized correctly with correct sharpening, placement of titles, etc).
On the release of every new module, I check if I can place an image or text block where I want to on a page. For me, this is a basic requirement. If that feature is not present, then I ignore the Lightroom book module for another year or two, ie until at least the next release.
There have been small, incremental improvements in the Book module over time, but unfortunately, this basic and most fundamental feature is still missing from the Lightroom book module. This is a pity, because 95% of the heavy lifting has been done.
I do produce books for Blurb printing using InDesign. I also plan to create handmade and hand bound books in the near future and will use InDesign for the layout and print the pages myself before hand binding. I also use InDesign to make up for deficiencies in the Lightroom print module, where I have automated the professional placement of Titles, Captions and other metadata, using a combination of tools, glued together by Javascript routines. InDesign requires a decent investment in time to use efficiently.
Both the Lightroom Module and InDesign need a “whole lotta luv”. The status of both products convince me that Adobe only provide lip service to the concept of workflow. What a shame.
If you have a specific question I will try to answer it.