With regards to Joomla essential, much of what you need to do content writing and suchlike is alread built in. Fantastic. And for delivering content to users, either registered or public, is great. However, I have to also use these components to make everything easier:
Chronoforms is a fantatsic tool not only for making contact forms, as it was initially set out for, but for making all kinds of forms, data inputs, registrations and database connections. Its WYSIWYG ajax form builder makes form building easier, especially with the build in mootools validation.
Alongside ChronoForms, Chronoconnectivity gives you the flexibility of data handing with a database to massive advantages. Anything you can do with a database you can make chronconnectivity show you. Add to this the seamless integration of ChronoForms and it is a formidable paring and definately my essential when using Joomla.
You can check this out at http://www.chronoengine.com