Mid_range pencils from brands like Staedtler or Faber Castel offer softer application, which allows you to get more color into the paper. This can produce a more vibrant color and reduces the chance of white flecks of paper showing through. Softer wax pencils are also better for shading and blending.
A few years ago, I wrote a book about realistic crayon drawings. What a joy it was to create, for I had brought my childhood dream into my adult professional life. I wanted to share it with others, for few knew that crayons are actually a wonderful fine art medium. They're not just for kids!