It starts from the first scene with Rey and Luke. We anticipated Luke's reaction to receiving his lightsaber back for two years and he tosses it aside. We have an emotional setup introducing Rose after we see Colleen from Iron Fist die. Then there's an hour of the Rose/Finn relationship that was irrelevant to the plot of the movie. If Finn sacrificed himself there would have at least been a payoff there (not that I wanted Finn to die). You have red herrings galore on who Rey's parents are, and then it's revealed that they're nobody (assuming we believe that's true). If Kylo was lying, then you wasted a substantial portion of the movie towards misdirection. You have the build up of Snoke and Kylo completing his training (for the second time if I'm not mistaken), and then you kill off the puppet master halfway through the movie (again, assuming he's really dead).
Lastly, they had an out for killing off Leia. It will be interesting to see what alternative they come up with now for Episode 9.