Your favorite paintings often have beautiful line. Confident linework is a skill developed over time. Start developing yours now! In Dan Marshall's video workshop, he says, “The more mileage you get with your brush, the quicker you’ll get to the point where you want to be at.”
Here's the tip: Put down your pencil and pick up your brush. Practice painting your thumbnails with your brush. It's a low stakes way to get in those brush miles. In no time you'll have the skills you need to start adding beautiful calligraphic marks to your larger paintings.