I'll respond in depth when more posters start sharing their thoughts, but overall, I was disappointed. I've been really looking forward to this movie and everything I saw in trailers/interviews seemed promising (other than the cast/leadership issues, which really showed). It's not that the story is weak, I didn't mind that, it's that so many scenes are so clumsy and unnatural. I just watched Toy Story and A Bug's Life and it's crazy how PUNCHY those films are. Every beat of every scene moves the story forward.
In The Good Dinosaur, things just kind of happen. For example, when Arlo meets the herders, they can't help him get to the mountains, but they are going to a watering hole where maybe someone can help, but then Arlo randomly sees the mountains and doesn't go to the watering hole at all ... Everything was just abrupt, coincidental, and loosely narrated.
I had other issues. Even the animation, which is mostly superb, was awkward at times, particularly the scene at the very end when Arlo is walking with Momma and Libby--the movement for all three at the same time was rough.
Anyways, while I'm disappointed, it was a very unique Pixar film. Arlo went through some CRAP and dealt with some very aggressively rendered forces of weather. I would definitely sit down and watch it again, hoping the non-visual aspects might've grown on me.
6.5/10, but rated it a 6 because I feel a little let down.