OpenDevEd has been streamling our Google Docs / Sheets / Slides workflows for many years, going back almost until the initial launch of apps script. For more details about all our Add-ons, see Our Tools.
BFormat for Docs provides a number of utility functions for Google Docs. In particular, it offers a coherent document style that goes beyond the formatting options available in Google Docs. For example, the various available functions allow styling of headers/footers and tables.
For details, visit our GitHub repository here google-apps-script/repositories and select BFormat for Docs.