1.
Color.
Mercury City tower in Moscow has gotten a lot of flak for its lustrous copper-colored cladding, but IMHO it's what makes the difference between a merely adequate building and one that rocks. If the same structure were clad instead in the generic bluish-, greyish-, or greenish-tinted glass used most everywhere else, it would be infinitely less interesting. In fact, use fewer tinted "-ish" colors altogether - it's cowardly. Compare Shun Hing Square's
green cladding with the green
ish tints of so many generic buildings. Off the top of my head, I can't even think of a truly blue skyscraper - blue like sapphire.
An important additional note to make is that white and black are also colors, and also have been neglected by the use of lame shades and mild tints. There should be
blinding white skyscrapers the color of some famous Greek Orthodox churches., like that on Santorini. Less off-white, beige, dun, light grey, etc. And there should be
black skyscrapers. Sears Tower and John Hancock Center don't even try to be truly black - they're just a kind of a dark shade of grey. I mean black like as if all light were annihilated.
Take a look at this new carbon material, showing the blackest black yet achieved in human technology:
(Credit: Rensselaer Polytechnic Institute)
I'm obviously not suggesting we coat a skyscraper in carbon nanotubes to achieve this, but it gives you a good sense of what I'm talking about in the difference between black and black-ish. Obviously, of course, dark black buildings shouldn't be in places where it would cause their AC bills to soar - I wouldn't expect them in LA - but they should be
somehwere.
Which is actually apropos of my next item. Skyscraper developers should stop being afraid of...
2.
Looking evil.
It's okay to build something that looks evil. It's just a building, so as long as the internal and street-level environments are genial, it's totally fine if it looks like something Darth Vader would build. The John Hancock Center in Chicago looks evil, but is endearing because of it. But architects are very reluctant to offer such visions because someone along the way might be offended or off-put by it, and that's just sad. We need more evil-looking cool buildings.
In other words,
There need to be supervillains in the skyline to compete with the superheroes. Angry red, pitch black, ghostly white, menacing tones of green or yellow coloration, awesome combinations thereof like the colors on a deadly spider's back, etc. would be how the supervillains would look, in addition to or instead of having evil-looking structure. Meanwhile, the heroes could have bold, life-affirming colors - the sapphire blues mentioned above, brilliant whites, bold life-affirming reds and greens and others, and blacks that communicate fullness or mystery rather than annihilation. The overall effect of doing this would be to add to the mythic atmosphere of the city, and create more energy and vitality.
3.
Being too good.
This is much more of a problem in NY than anywhere else, but I'm sure the other skyscraper cities of the world will eventually run into it: Designers and developers being reticent to propose something that's
too good because its awesomeness offends the piety of some existing landmark building's cult that feels their building would be outshined - which, of course, also means its owners might have a dip in property value (though rationally, two great projects near each other could easily increase the value of both). That seems to have been at work in the downsizing of Tower Verre while at the same time allowing a relatively fugly project like 15 Penn Plaza to stay at ESB-level heights: They will let you challenge ESB on height, or on beauty, but not both at the same time.
This is not a good state of affairs. There are plenty of economic reasons not to strive to be the best, but never, ever, should one of those reasons be a desire not to compete with an existing building for awe and majesty. Any project where beauty is any priority at all should strive to be the best that it can be, not knuckle under to sacred cows on behalf of Byzantine politics. So,
if you are going to build an ESB-class scraper near ESB, build it to look better than ESB - don't cripple it out of medieval piety. Don't be the guy who deliberately loses card games to the boss. Don't be that guy. Use every project as an opportunity to make progress, push the boundaries, explore more profound domains of beauty and grandeur.