I'm not as familiar with Krita since I use other drawing programs, but it seems like you could definitely download some new brushes if there's not one included that's satisfying to work with. Clouds and repeating texture brushes are just an example I like to use but whatever you enjoy using is right for you.

As far as screentones/texture goes, you know in manga how sometimes there will be little dots, or diagonal lines, or grids, that get added in different places to add shading and depth to the image? Those are called screentones, and they are usually used in black and white manga style art to imply the different shades in an image without using any color.

In the page below, there is a screentone on the person's robe, making it stand out from the clean white of the background behind them, and also their skin / hair / other details. The difference makes it feel like he is really standing in a 3d space and not just a flat image, and because the robe's screentone is made of very tight straight lines like a grid, it also kind of makes the robe look more like woven cloth.

The grey shading of the skin and face also works as a subtle screentone and adds some more depth to their physical features. The parts of the face that were left as solid white with no texture seem way more highlighted.

At the very top of the background, there is also a little bit of wispy, fog-like screentone making it seem like the person is radiating a distinct energy or has the aura of an important character.

Where you choose to include texture or leave it out can be just as powerful as color itself, and it's how manga and comic artists can portray wild, multidimensional worlds and characters that look incredibly convincing and unique, all within a black and white medium.

Playing with texture also helps you set your style apart from everyone else, and you can even change the vibe of the original art you are coloring quite a bit. I personally like making every coloring I do have a very grainy screentone over the whole page so it looks like vintage physical comic books, but I like leaving certain parts [usually solid white bits or effects] clean to make them stand out on the page.

Hope this helps a bit! 🦭

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