Illustrators and fine artists have been turning out tons of innovative architectural ideas for at least 120 years, but very little of it has been taken seriously by professional architects. I believe that their neglect is about to turn around, and in thirty or forty years a feeding frenzy will develop among architects for 20th Century art and illustration to crib from.
The reason I place this frenzy 40 years in the future is that some of the technology that'll enable it isn't in place yet. Take the Mary Blair painting above. Right now nobody could make an elevated train and tracks with a black as rich and saturated as the one above. Nobody knows how to make white light like the white in the train's windows...I mean white like the pigment, and not just sunlight. Nobody could do what Blair did and make the sky near a building black, even at night. Nobody could color a real building with the vibrant colors available from a tube of gouache. But they almost certainly will.
Have you seen the TV documentaries about the military research currently being done on bending light in order to render some colors nearly invisible? That's a neat trick, and it'll eventually pass into peace time civilian use. Depend on it, the same science that allows us to subdue color will enable us to enhance it. Expect to see Mary Blair's ideas made more real than any of us could have imagined.
BTW: Thanks to Amid for the picture above.
Here's (above) another Blair picture. I I like the way Blair subdues the background buildings by making them shades of blue. It makes for nice contrast. The day will come when distant buildings that appear blue from our vantage point will become colorful when approached, and buildings that were previously colorful will become blue as they recede from us. I'm not talking about the misty blue brought about by aerial perspective, I mean saturated blue, like the pigment. The people actually inside the building will see no color change at all.
What I'm saying is that the not-too-distant future may bring us subjective color, which is experienced differently by different observers standing in different places. Interesting, huh?