Using the classicthesis
package with unaltered margin settings for paper size A4 results in the following page layout
The right margin is visibly larger than the left margin. When finally printing and binding the document, the difference will be even greater because the shown page will be bound on the left side.
I know that I have not nearly as much experience in typography and layout than a professional, but looking through some of my books showed in general a different layout. Knuth, for instance, has almost the same margin left and right (close to 2cm left and about 1.9cm right). My final document has 3.3cm left and 6cm (!) right margin.
I'm not saying that this probably isn't okay, but it really looks weird to me. Are there better settings for A4 paper? I would rather prefer when the text is centered in the final printed and bound document.