"The pictures woo the ladies but men want content, we know that a hosta may only look that way for one week in spring."
What kind of a remark is that??? Does he take us women as complete fools? (rhetorical question - obviously he does!) It's hard to take someone's review seriously when they show this kind of poor judgment.
As to the arrangement of the plants, I think this is a fine way of doing it - if you're looking for a hosta of a certain color to complete your landscape, you can look in that color section (the colors are defined broadly enough that you should be able to find the right chapter) or if you are looking for a specific hosta, you can look it up in the index. Seems very flexible to me.