Yep, they have a tier system. I think
@PolyRob posted the tiers sometime back. It would be nice if with the new Toy Story Land, one could book say all three SDD, TSM, and the Alien Swirling Saucers (better not put the acronym here unless I want to be flagged!) But, the Toy Story Land rides are all in the same group! I would prefer to rope drop the Rockin roller coaster and Star Tours, and then have FPs for Toy Story Land. That would be how I would want to do the park. Hollywood Studios is my least preferred park, I hope when the whole Star Wars land gets added I'll feel differently about it.
I hate the tier system, because the things I want to book are essentially in the same tier. Thus the reason, I'm sure I'm not the only one. However, wish Disney could come up with another plan on those.