Traditional line work* (particularly for long comics).
When I first started my comic, I decided to do a mixed media approach with traditionally inked line work and digital coloring. At the time I hadn't done much digital art so I didn't feel at all confident in my digital inking, but I wanted to color digitally to save money in marker ink. At first I felt really good about the decision- I totally felt like my traditional lines blew my digital ones out of the water, but I still got experience with digital art through corrections and coloring. win-win!
Buuuut somewhere around the halfway point several months in, I began to realize how inefficient it was making my work flow. If I spent a long time on the sketching phase, that just left me with a bunch of pencil to erase after the fact which took time and often left residue on the scan, when I Swapped to blue pencil I removed that, but it was hard to see, when I swapped to digital sketches, it was almost perfect but a little hard to see through my light box. Then I only have a small scanner, and 11x17 paper, so each page would take 4 scans.
Further, through doing more digital art (and getting a tablet upgrade at one point) as well as playing around with some custom brushes, I felt my digital inking catching up to my traditional inking.
A few of my friends were like "why don't you just swap over to digital? no one will mind." But I was close enough at that point to the end (~2/3 through?) to commit to finishing it out with the same work process, for consistency and all that jazz. Then they called me a masochist
I finally finished the 70 page comic last week:
On one hand, I'm glad to have stuck it out so that I have this complete pile of original linework that I can hold in my hands, show off to people, and use as a self defense weapon if need be (it's HEAVY). But at the same time, I'm soooooo going all digital next time LOL. Traditional will be reserved for short comics in the future (and probably only when I want to do traditional coloring too).