Cranes, and rooftops, should be decorated
Look at the skyline of any growing city, and what do you see, but a sea of construction cranes. The theory is that each crane will go away and be replaced by an architectually interesting or pleasing building, but the cycle continues and there are always cranes.
My proposal: An ordinance requiring aesthetic elements on construction cranes. Make them look beautiful. Make them look like the birds they are named after, or anything else. Get artists to design them as grand public art installations. Obviously you can't increase the weight a lot, or cut the visibility of the operator too much, but leave that as a challenge to the artists. And give us a city topped with giant works of art instead of eyesores.
While we're building these skyscrapers, it seems to me we also don't seem to care about the aesthetics of our cities from above. The view from the towers, or incoming aircraft bringing in fresh visitors, is of ugly rooftops, covered with ugly pipes, giant air conditioners and spaces everybody imagines that nobody sees. Yet we all see them.
Compare that with many European hillside towns where everybody knew they would be seen from above. At least in the old days, the roofs were crafted with the same care as the house. Today, that's been changing, and many roofs are covered with antennas, satellite dishes and in the middle east, black water heaters. We care a lot about how our houses look from the curb, and we imagine people don't see the roof. But we do.