Not surprised this happened. Anyway
-The NCR has vertibirds, why not bomb the Legion's fort?
You see one that is the president's personal transport. I doubt NCR has an air force. The ones they have they have took over from Eclave bases, so the number and the supplies to keep them running may be quite limited.
- Just what is the timeline for vault 34?
Now that is a good question. That whole thing makes no sense. But because it doesn't, i can always think of the message as years if not decades old and the people long gone, and go ahead and make the decision for the greater good
- How did the vault 19 powder gangers get past the supermutants/deathclaws?
Maybe they moved trough before the Deathclaws took over the quarry?
- How does the BoS get food?
Veronica mentions she's gathering supplies for them, and that she's not the only one to do so. Also theose "hulking figures in the night" may be raiding for supplies too.
- Why does Caesar tell even the most anti-Legion Courier to go alone and unobserved to destroy the Securitrons under the Fort?
Someone explained this once, that he didn't want to see his men to see what's down there for some reason. I don't remember excatly how it went.
The whole story is about Hoover Dam and it's power, yet all powerlines are down. Also NCR supposedly uses trains to move the concrete from Quarry Junction to Boulder, yet the train tracks are covered in sand in many places.