I struggle with them!
I really struggle with quite how much detail I should put into them. I don't want to spend all my time focusing on them, and also don't want them to detract from the main focus of a panel, but also know that in what I'm doing, they're necessary for creating a sense of place and for characterisation and mood.
But I get caught up on trying to make everything fit the correct perspective and then I get stressed about it, even with simple backgrounds.
I want to get better (and quicker) at them though!
Some people are using 3D modeling to help, but I have absolutely no knowledge of how to create a 3D model of a background or even a single element so I'd have to learn that and I want to be drawing, not learning a completely new program.
Maybe it's time to bite that particular bullet though...