You never get to see any Oblivion gates if you ignore MQ. In Skyrim, you don't get to see any dragons and noone ever including yuourself finds out that you're special, if you chose so. So in both games it is still possible to ignore the being god-sent whatnot thing, and to start out as an ordinary guy/girl.
Kvatch is destroyed regardless of your actions. Sure the city is for some reason entirely irrelevant in the game, doesn't even have guild halls, merchants or anything of importance but should you go there you will still find yourself facing Mehrunes his army.
Actually, I'd say they weren't chosen. They were false incarnates, people who believed they could but failed to fulfill the prophecy (and you can't be The Chosen One to fulfill a prophecy if you can't fulfill it). If I recall correctly, they all died when trying to wear Moon-and-Star, which clearly puts them in the not-the-Nerevarine camp since Azura didn't allow them to wear it.
Few quotes from the incarnates in the cave:
Hort Ledd: I died four hundred years ago, in the last days of turmoil and unrest after the Empire came to Morrowind. I was a thinker, and not a doer, and though I was marked by the stars, I was not a hero. Take these things of mine. My bones won't complain.
Peakstar: I am a failed Incarnate. So are all these who remain here with me in the Cavern of the Incarnate. I survived the blight, but I fell in battle with an Ash Vampire. I could not master the arts of war. Nor could I learn the ways of the Great Houses. They would not have accepted me as Hortator. Take these few poor things... they are of no use to me.It doesn't necessarily prove that they were meant to be the moon and star, but not a single of the failed incarnates died when putting on the moon and star, hell it doesn't seem any one of them even tried. So that's not the reason why they never became the Nerevarine. They died in combat, so I'm still left unsure here. I also don't understand why Azura would ever allow a bunch of imposters in her cave after their deaths, or why their souls would be bound to Azura.
At the same time Peakstar was the last incarnate before the PC, and everybody seemed to believe they fit. Yet the Wise woman needs to get guidance from Azura before admitting that you might be possible, you'd think she would have done that with every incarnate.
By Ashlanders, who also see "Nerevarine" as a title for their war-leader. So even if you are a reincarnated Nerevar, you don't become the Nerevarine to them until you prove yourself capable.
I'm a bit curious about what the -ine suffix actually means though, since TES is the only place I see it to mean 'the reincarnation of'. Perhaps it could be that "Nerevarine" does not strictly mean "the reincarnation of Nerevar".
True, that makes a difference. I just always assumed the -ine meant incarnate, don't know why but it made sense.
The CoW, DB, and TG for sure, but I wouldn't put the Companions there.
Spoiler Their biggest issue is over their lycanthropy, and the biggest problem spawned by that is their rivalry with the Silver Hand. The Companions have shown themselves to be able to handle the Silver Hand. The only two that died are Skjor, because he's a hot-head and carelessly rushed into a fort filled with them, and Kodlak because of an unexpected attack in the middle of Whiterun. I'm sure they've had members get killed on the job before, and the SH don't strike me as particularly threatening to the guild as a whole.
Whether Kodlak's and the twins' lycanthropy is cured or not has no real bearing on the survivability of the guild. At least, I didn't see any such implication. Since Aela survives and remains in the Circle with her lycanthropy, and the player can also, I think it's safe to say the Companions aren't done with their lycanthropic "problems" yet, either. Really, by the end of it not much has changed with the guild except for the loss of Skjor and Kodlak, and the dismemberment of the Silver Hand (who were more like a thorn in their side instead of a serious threat).
Spoiler
That is true, but the Silver Hand would have attacked anyway and you are the one that is tasked with taking out several of their bases. So their attack might have been more powerful, you are right however that this is not something they could have done without you.
Kodlak sees you in a vision that he writes about in his journal however... So you are destined to save him at least. It's not the same you are right but still you have a destiny there for some reason.