Illustrator for drawing

In my field of writing, being able to draw is not exactly a requirement. Where words cannot describe what I want to show it is always important to be able to show.
Adobe Illustrator has been a very popular vector based drawing tool by Adobe for years. Preferred by professionals, I've only begun to dabble in it recently to explore and see if I can widen my existing toolset.
Had tried it before but was annoyed that it wasn't like tools I used before like Photo shop, admittedly both slightly different tools. Then I googled for Pen tutorials. Started a few simple tutorials and soon saw some potential.
I stumbled on this fantastic technical illustration tutorials which are quite hard to follow at first, and then it occurred to me that this would be a very important skill to have, in future.