Couple a thoughts - weirwoods would need to be alive to part of the net, yeah?
Arya stands in front of a lot of weirwoods, so Bran could at least know she is alive and not at Winterfell (she ain't Jeyne getting married) but Brienne's discussion with Shagwell about the Hound having a Stark might confuse him.
The chapter with Beric fighting the Hound is bizarre. He is positioned like Bloodraven on a weirwood throne and the CotF says that Rh'llor magic does not work around the old gods, yet he is brought back to life..... so Bran might need to track Dondarrion down (if he is still alive), or at least find Catelyn.
The chapter with the Blackwoods is interesting because Jaime is meeting Bloodraven's relatives, who we could presume have some inherited traits. Keep an eye on Jaime's hostage perhaps. Sure are a lot of wargable ravens in that god's wood.
I think the Nightfort and the Black gate (Black Gate, Blackwood) are super important as Bran will piece together the links between the Cotf, the Others, the Last Hero and the Night's Watch, and may have to start rounding up a team to go kick some Other ass.
HOWEVER - if Bran can warg ravens, he is also going to find out a lot by listening to messages being read out.
MAJOR HOWEVER - All the ADwD chapters are really, really dark and foreboding. Jojen and Meera get really depressed after they arrive (and disappear before Bran eats something that has blood in it), there are lots of bones including human that the guide doesn't want to show them and Bloodraven tells Bran not to fear the darkness, to list but 3 examples. So the main revelation Bran needs to have is that he has walked into a trap and he will have to get out of that before he links up with Jon and is team of Zombies.
Well that's what I think..