Its pretty fun, the base class stories are all really good, and now that they've streamlined it you only need to do those ones to hit level 50. Used to be that you'd do the class and then all the planetary quests to get decent exp. lmfao
If you subbed for a month, you'd unlock the Knights of the Fallen Empire and Knights of the Eternal Throne expansions, which are both fantastic stories to do after the main class stories are done.
I'm not sure if they made the earlier expansions free or not, but they were both pretty good, one of them even focused on Revan. :v