I painted this cactus in thick acrylic paint because I love the texture of organic brushstrokes.
I don’t vectorize my watercolor or acrylic paintings because the vectorizing process erases the authenticity of my original painting, especially when it comes to brushstrokes and the textural details.
Instead, I scan the artwork in at a super high resolution, and printing raster designs on products has never been an issue. It makes for some pretty massive files, but for me it's worth it to keep the integrity of my hand-drawn work.
Lots of people think that in order to license your work, it MUST be in vector format. But that's hasn't been the case for me. As long as your files can be scaled up without losing their quality, you'll be good to go.
If you want to learn the difference between raster and vector files and which is best for surface design, I wrote
a blog post with all the details!