I have long admired the style of modern images made by these rounded "pill-like"forms. Just how to understand the construction a composition by a master illustrator? That is the point of recreating this image - not just it as an detailed analysis of the image itself, but also exploring how features of Adobe Illustrator CC can be best utilised to create desired effects.
The Blend tool was a superb instrument in creating regular patterns, as opposed to my first choice of creating a position Transform and repeating it. So in the example of the welded poles, the diagonal details were formed by two paths at the extremities, and the Blend tool used to create regular iterations. Eventually these were broken out using Object: Blend: Expand to form the individual paths, and those then expanded from paths to filled objects. The pole form was a heavy path with rounded caps which was then expanded, and this used as the Clipping Mask (Cntrl 7) for the diagonal shapes.
Blends also came into their own in the details on the buildings. This was true of the horizontal and the vertical decorations. I tried using the Pen tool for the horizontal rows, but the Blend tool was more precise.
In conjunction with those Blends, the Shape Builder tool and the Live Paint tool really came into their own, as well as the Path Finder options.
The gorgeous "white mask form" was created by using intersecting circles. Clouds also were formed by intersecting circles, which were then merged into nice bubbly forms - the lighter clouds had a horizontal line cutting across them - and Shape Builder tool with Alt Key to subtract the extraneous circle forms below the horizontal.
This was a purely didactic exercise, and I gained a huge amount from working on it in terms of exploring Illustrator tools and effective workflow.