The additional quests are stand-alone modules that take place years before the events of the story. When you start them, you will be given some talents to spend on your character - they are fun for a short distraction but nowhere near as good as the main game. In fact in many ways the short modules really show off the short comings of the engine.
I would only recommend playing them after you are done with the main campaign and are hungry for more of the same combat style. There are some other better modules out there too.
Two wrongs don't make a right... but three lefts do!
If beauty is in the eye of the bee-holder, then why are hives considered unattractive features?