I'll only post some early thoughts on the NRJ before revisiting Pandora and reviewing the entire thing.
I really liked this attraction. There is pretty much nothing wrong with it.
The issue I think it is having are two fold:
1. People keep trying to wish it into something that it isn't (i.e. An E or really even D ticket).
2. C tickets ARE NOT worth 90+ minutes waits.
The ride more effectively demonstrates the bioluminescence than the physical land does, I love the loose narrative. I really didn't feel like it was too short in the grand tradition of what I expect from a supporting attraction.
I also had the benefit of having it be a FP AND having it be an actual walk on during the evening EMH. So needless to say I hope I got to experience it closer to reality when the waits calm down and it spends most of its time sub 20 minutes. It's a beautiful, well executed non-headliner. Really, one of the, if not the very best C tickets Disney has ever produced worldwide. This was also something sorely missing froM the AK menu and it fills the gap fantastically.