Oof! I believe you can practice using brushes to get better! After all, practice doesn't really make perfect, it just makes you close to perfect!
Also, watercolor markers? Wow.. I've heard of watercolored pencils, but not markers. These would be great to try out, since I'm a huge watercolor fan...
Hello, FishFin!
I love your art style, but I also want to give you some tips, artist to artist.
Instead of using markers for the outline, why not try fine liners? To get the brush effect, just get a brush tip! I use fine liners or multi liners to outline my pieces, and they look really good...
I always find it amusing how people say that they can't draw. Since "draw" means producing a picture with lines and shapes. It doesn't have to be a masterpiece. It's drawing, right? As long as you practice, you'll always get better.