^I read the graphic novel kinda quickly and I didn't pick up on all the visual stuff. (It's a side effect of me mostly being used to reading prose.)
That's why I've suggested not reading through it quickly. I got a few "flames" a few posts back on this topic for suggesting that the way to read the story is to read each chapter... in depth... then go back, a couple of days later, and read it over again, in depth... and then to read the "supplemental" stuff... and only then go on to the next chapter.
The little things like Veidt's perfumes and colognes being in virtually every scene, for instance... you have to wonder if there was anything fishy about that. I mean, if the guy is selling, for all practical purposes, all the perfume being used in the city... what happens if he starts putting a hallucinogenic into it at some point, just to help with the whole illusion bit for the "big show" he's got planned?
Notice the changes after the "event" versus before the event. There's a LOT of stuff that's different.
Notice the omnipresent geodesic domes throughout New York City. That's not just tossed in, it's addressed, but in very subtle ways.
Note the stuff in the background shots when you see the kid and the magazine vendor. They're sitting right outside the "Institute for Transdimensional Studies." So the background shots are at least as interesting as the foreground... especially when compared to some of the shots on the island.
The thing is, this is a remarkably rich, well-thought-through story on all levels. I know that huge amounts of that will inevitably be lost, just by virtue of the story being pared down to 2 hours. But it's all still in the book... so TAKE YOUR TIME, and read it slowly and carefully... and be prepared to go back later and catch things you'd never noticed the first time (or two, or three).