Hello, JanekZ!
Be careful with consistency in managing the paragraphs. Use either indented paragraphs, or split all paragraphs with a line space. On your page you have three different paragraphs: indented, separated by a line space, and that final "Enjoy...", not indented and not separated.
Also try centering the "Preface" and the folio on the text box, not on the page - it might look better.
Otherwise the justification looks quite good. Try showing us a page spread.
I agree that the text seem heavy, dark, and even a bit awkward. Maybe cosmos isn't so good for books. I wonder if the average reader would get distracted by the design of the typeface?
The text box is OK although it seems like the top and bottom margins are nearly equal and the right margin could be a bit more generous.
That grey bar at the top is sort of clunky. Really, you have 3 important elements on a page like this -- the text box, the header and the folio. You can work these 3 elements to make something quite nice. The grey bar is superfluous. As it is, I see something rather default, ie: folio goes in the centre at the bottom. You could try something else.
As a guide book I imagine the other pages are a lot more complex and will require fine attention to the typographic details. Have you worked on the hardest pages of the book yet?
I love climbing, mountaineering and wilderness guide books. Unfortunately they are almost all quite horrible to read. So please make a nice one!
More on Cosmos: I looked again and I don't think its up for the task. Does it have small caps, and non-lining numerals?
At the very least you've made me want to visit Kazalnica.
Thanks guys!
New pdfs attached.
Steven > It is 9 pt and minimum to read without artificial aids. Unfortunately pdf is awful in comparison with printout.
Todd > "That grey bar at the top is sort of clunky." I need something distinct as the new chapter beginning. Maybe some white space will be enough.
There is my printout vs SMITHSONIAN

"At the very least you've made me want to visit Kazalnica."
Hereyou can see my topo/poster with winter routes on Kazalnica.
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