Just a quick piece of advice because I have seen so many dark characters drowning their lineart with their base color and this used to be a mistake I made when I was younger, too.

If you have a character with very dark fur, hair or skin color, consider making the lineart lighter to preserve detail and visuality.
Depening on the choice of your color, you can even indicate the hue of the base color with the lineart!

From 2021