Comment on Mangaka-chan's profile
I usually trace reference images I find online for really complex backgrounds/architectural elements. 
I can kinda-sorta manage simple perspective drawings, but anything more complex and I'm out of my league.
I have Manga Studio, but I found it a pain to use, because it takes forever to load screen tonesalthough this could be because my PC is really old. Instead, I do all of my line drawings on SAI, then add the text, patterns, and screen tones on Photoshop.
I can kinda-sorta manage simple perspective drawings, but anything more complex and I'm out of my league. I have Manga Studio, but I found it a pain to use, because it takes forever to load screen tones
Thanks for the tip. That's what i usually do as well. I never had the chance to use sai because it doesn't work on macs. Your lines are very clean so different from me lol.