I absolutely love your art style! Have you ever thought of trying vector art? It will make your lines flawless and you can use a mouse to make it too, no tablet required.
There are a few free programs out there if you look. Inkscape is for free but it's not user friendly.
I usually like to use Opentoonz more even though it's an animation software.
And if that sounds like a challenge learning a new software Youtube is full of free tutorials that teach almost any software.
Keep at it, you've got lots of potential!