hmm, i know this is an old post, but i would like to share my insight if its ok.
I was in your predicament for a while too. Drawing, like many things in life,, is all about self discovery. If you find yourself getting bored, its ok to take a break from drawing and do something else. If you find yourself drawing in a particular way, thats fine too because then it becomes a part of your style.
Also, dont concern yourself with how perfect your line-art is. Practice will make you improve regardless. Focus more on drawing artwork that pushes your boundaries or draw something that makes you excited, and work on it no matter how it ends up. Sometimes, so called "bad" artwork is some of the most unique and badass art pieces people can look at. No one proved that more than ONE(creator of one punch man).
When he first debuted, even in Japan, people were telling him his art was ugly and he would get nowhere with his comics. I think we all know where that went, lol.
Sorry for the long comment, am I helping?
AdventVoice
Practice makes perfect. When we desire to get better, we find that we do. I know we hear it a lot, but pure dedication is what it takes to achieve certain levels of line craftsmanship. I like a lot of your works though.
Spedmallet
All true. And thanks.