I came across this Medium article yesterday. Matej Jan tells the story of how he went from a PC heavy artist and illustrator to an iPad based one. He has found that the iPad and Apple Pencil has improved his work life in ways he didn't expect.
Matej use the iPad in many ways, including as an external screen for his MacBook and as a replacement for a Wacom graphic tablet.
There are lots of images, photos, references to apps and some accessories throughout the long text. I found it well worth reading. Perhaps it is even more valuable and inspiring to someone curious about what it can be like to work with an iPad as a main computer. For designers, illustrators and other creative people I think it should be a must read. :-)