How so? It wouldn't have made a difference if they all those who vanished simply died on the spot for some medical reasons.
Garvey is dealing with domestic stuff of his wife leaving somewhere after he cheated on her. He is also presumably battling a potential mental condition.
Tommy and Wayne stuff aren't connected at all with the disappearance.
Nora lost his family. It could be exactly the same if they died suddenly.
The priest is concerned about letting everybody know the part of the vanished were bad people so we shouldn't revere them etc. The same could have been if 2% of the population died at the same time. People would still be trying to cherish all those who passed away randomly or ascribe to it meanings.
Same goes for the GR. Not letting those people who died be forgotten.
Religious people could still act religiously about that massive death. But the fact there are bodies and all died from the same medical condition would lessen the heavy religious emphasis the show currently has.
You could probably eliminate the 'something happened to 2% of the world' and still have the show be more or less as it's been. Or have something like a plane that flew out in Christmas night, that passed over some religious landmark in its flight, has landed with all the crew and passengers found dead or with them not in it to keep that premise of something X happened to Y people that The Leftovers is using.
So far i really don't see how the specific premise the show has taken (haven't read the book) is enabling or magnifying what has so far transpired. In face, the detail of the vanishing of people into a thin air gives fuel to the religious and mystic underpinnings of the show that to me is part of what i dislike about it.
Firstly, as you clearly are aware, this is adapted from a book. Lindelof didn't choose to have them disappear, that's what happened in the book.
Garvey is living in the shadow of his father, having assumed his job and home following his father's mental breakdown, which was seemingly related to the incident.
Wayne is a healer, specialising in comforting people affected by the incident, as has been having prophetic dreams since, presumably only gained his 'ability' since, but we don't know that yet.
Nora is a woman. She would have been upset if her family all just died, sure, but she's famous amongst the town because of it, she's the ultimate victim of the incident in the town.
The Priest I kind of just disagree with. Yes, if 2% of people instantly dropped dead, some people would still believe it's the rapture but I doubt it would be to the degree that it is. It also raises the point that how is that better? How is the population just magically instantly dying any better or worse than them disappearing?
I don't feel like GR's motives are really clear enough yet, but none of them have really registered as characters to me, besides Garvey's wife.
And the final paragraph seems to indicate you already know why they disappeared instead of just dying, because it does more heavily suggest a magical/mystical event. The whole titles sequence screams the rapture, the show wants you to think it's that. If you don't like that, that's fine of course, but you clearly already know why vanishing is distinct from dying.