I found the comments on the layout of Bestiary of Kyrnn to be really interesting, so I went back and compared the two books. Two things jump out at me, and they are connected by how the two different pieces of software work.
0) InDesign is perfectly happy drop a big picture in the middle of the page and flow text around it. If this is what you want to do, InDesign wants you to be happy. LaTeX (the "text book" software) doesn't like to do this. It has very specific ideas about what makes for good layout and will contort itself (and your documents) if you try to do something which it thinks is bad layout. It does not want you to shot yourself in the foot.
Once you know to look for it, this really stands out in the two books. The first book confines all its art to be either in one column or to take up both. There are no pictures straddling the divide. No text flows around pictures. Text stops, you get art, then text resumes. In the second book art is splashed on the page in "dynamic" ways. It straddles the column divide taking up some of the space in the columns to either side, or it stretches beyond one column to take part of its neighbor. Text flows around it on one or both sides.
1) The first book, the one done with the "text book software" turns stat blocks into literal blocks. The color shading is a bad choice and the column alignment is a little jarring to read. But they are clear, uncluttered, and don't make the DM work to read them. They show up at either the top or bottom of the page, but don't hang out in between. They don't span pages or columns. Maybe not the best, but they don't suck and are fully functional. Makes life easy at the table.
2) In the second book, stat blocks are not literal blocks. They start at whatever point in the text the description ends. They span columns if that's what they need to do. And they get crowd out by the art. In several places a monster picture straddles the page divide, forcing an entry in the stat block to half a column of width, where it flows on to the next truncated line. When the stat block falls to the right of a picture, this means that the field headers are not justified against the right hand side of the column but instead form a ragged line as each one is pushed a different distance out of place by the art. This is terrible, awful design and makes them hard to use.
Aesthetically, I guess you can take your pick. I think you could make an argument that the second book is prettier. But functionally, the first book is far far better.
