Well, not really. Previous time-travel adventures have all dealt with making sure that the time-line is preserved.
I semi disagree with this. Trek has had a whole lot of different ways of time travel and how to deal with it. One of the most famous time travel stories of all, TVH, wasn't about restoring the timeline at all. Heck, it seems that if time took its natural preserved course, humanity would've been doomed. In Generations, had time not been altered, the Enterprise-D crew and Veridian III would've been doomed.