You will likely find 60 cm (24") is too shallow for the desk top. Previously, I had a 30" deep table, and replaced it with a custom built 36" (~90 cm) deep workbench. I like it better. If you have literally no equipment on the desk top (like rdl has in his photo) then a shallow desk works OK. But, if you have your soldering station, parts drawers, or anything else along the back wall, then consider making the desk deeper than 60 cm. The depth of the equipment you use also plays into the work surface depth. I have many old instruments which can be as deep as 60 cm themselves. Obviously, a 60 cm desk depth with 60 cm deep shelves wouldn't work. On the other hand, if the equipment is shallow, then the shelves can be shallow (again referring to rdl's post as an example of that).
I have my first shelf top surface at 18" (~45 cm) above the work surface. This puts the equipment on that shelf directly in my line of sight when looking forward (I am tall). I have a second shelf above that, which is at a nice height to operate equipment while standing. The lower shelf is also at a reasonable height for standing operation. It is less practical to use the upper shelf while seated. Each shelf is tall enough for a 6U-tall stack of equipment (2 to 3 typical instruments or one large one). A third shelf above everything is for storage and has no equipment. Someday I'll clean up and take photos.