I'd personally wait it out. Last year was a different story (I bought the PS4 exclusive when I have an Xbox360) because we got the collectors base. Every thing in this pack will eventually come out.. And think about all of the launch figures we are getting... 5 emotions from Inside Out, 6 Disney Toy Box characters, 4 Rebels characters, 4 Twilight of the Republic characters, and maybe the Marvel playset which would be another 4 or 5. That's over 20+ characters that you can play with at launch! Would you really only be playing with Boba Fett on day 1?? Besides, the PlayStation Saga pack doesn't include Chewie, Han Solo, or Darth Vader, would you want to play through the whole playset without them (Depending on how fast you play through it)!? I know that I wouldn't. That way it spaces out, instead of spending everything at once and saying "Now what?" I can buy my Inside Out figures and still think "I have a new Star Wars set coming out next month!" And after I'm done playing that I can say "Boba Fett is next month!"
With the Marvel play set, Twilight of the Republic play set, Toy box takeover, toy box speedway, Inside Out play set, I think it may be January before I even get into playing Rise Against the Empire, which would then be the perfect time to by Boba Fett at regular price.
.....or you can spend $40 extra at launch