When you copy and paste the text into your documents it is often passed along with various formatting, font styles, etc. You may quickly clean it up using a hotkey.
Instead of creating going to Google Docs, you may use a special link that was made by Google to speed up new document creation
When your document is long, you may quickly navigate between sections using navigation automatically generated by the editor from headings in your document. It collects titles and headings and you may jump between them.
If you are using a lot of links it is useful to use a hotkey instead of right-clicking with your mouse.
You may use comments as to-do tasks and even assign them to others.