My graphic novel has all hand-drawn backgrounds, but I've done a lot of 3D and photomanip backgrounds in my webcomics, and my belief is:
What's faster than painstakingly measuring, plotting out, and drawing a clean, complex, accurate architectural background by hand is building it in 3D.
But what's infinitely faster than building it in 3D is drawing it bad and wrong. :)
I'm joking a little when I say bad and wrong, because 9 times out of 10, the bad and wrong background is the one that actually looks the best. But that's the point.
It took me a really long time to get out of the trap of thinking my backgrounds had to be "correct." Thinking stuff like, "Well, this shot is rotated 30 degrees from the previous shot, so THIS is the correct background angle to show for the next panel." And no, actually the correct angle to show for the next panel is whatever looks the best.
"But the painting hangs THIS high on the wall, so it needs to be HERE behind the character in the panel." Nah, it can go wherever it gives you the best composition and doesn't create any tangents, or you can just not show it.
It doesn't have to be right. It just has to not be distractingly wrong.
Yeah, there are always caveats and exceptions. Like, I have the luxury of having a flatter provided for me for the GN, which means it'll be MUCH easier to color those backgrounds (which will only have limited color anyway). Also, settings that repeat a lot are great to map out in 3D even if you only casually reference them, and it can help you visualize the space and come up with creative angles. Some things are just a million times more *fun* to build in 3D. The experience I gained working extensively in 3D for over a decade is part of why my current bad-and-wrong backgrounds look better than they would have looked in the past. And, as always, different approaches work with different styles.
But, of all the reasons one might have for working with 3D backgrounds, I've come to believe that the least necessary reasons are because they are clean and accurate and correct.