spacehamsterZH wrote...
Eh, sounds about like the same type of nonsensical 11th hour plot twist.
Really, what I'm left with here is that either a) they had no idea how they were going to end the trilogy someday back when ME1 was written or
it was always the plan that in some form or other, it would turn out via some last-minute plot twist that the Reapers are necessary. I don't know which is worse.
When you start writing a saga or an epic TV show and you already have the ending in your mind, all that you get is stiff writing. I often read about a TV show called FlashForward, being an example of that sin. The writing team had planned everything for a few seasons before the pilot even aired. So, they had no opportunity to wonder if some elements really worked, or change their minds at some point when they move forward with the scripts or with the dailies that showed the actors' take. All the big decisions had already been made. And the show naturally lasted one season.
The other approch is to make up entire parts of the mythology as you go along with big scale projects. Lost did it, Star Wars did it. Drew Karpyshyn admits for instance that Cerberus was something vague and secondary in the story until they started writing ME2. Almost everybody does it.
The result is that almost every conclusion of an epic story is a disappointment, especially in sci-fi. When the fate of an entire civilization or galaxy is at stakes and that you tell that story through a few select individual characters, there comes a time when you can't simply keep the balance between the two levels.
So a) and

are actually perfectly compatible. I guess that the idea of a final twist concerning the reapers was written as a template from the very beginning, that they focused on developing the entire ride and that they couldn't find a more satisfying ending. They focused on the ride, the journey and in the end they chose to do some generic thing, using an higher being to give some kind of perspective to everything, because they couldn't find a better way with what they had.
For the record, I completed the game last night and I'm actually not angry about the ending. I just found that the cut scenes about the Normandy crashing on a new planet were coming from nowhere and were ridiculous, bordering on offensive. The child being the avatar for the "higher being" that inhabits the Citadel and the final choice are only formulaic and quite lame. But, at the moment I had a talk with every mission character alive from ME2 and ME3, I accepted the idea that Shepard would make the ultimate sacrifice and would die. That was the real closure for me.