yes Fain was unique
Which on the one hand makes sense that his ending needed to be uneventful if the end of the age wasn't to be any different.
But on the one hand, Fain is the key to so much of the books, without him things would be very different.
All I can think of is that Mordeth is...
I feel that it important to try and move away from the simple image of a "wheel". It tends to dumb down the situation for most people to be more simple that it really is.
RJ put it nicely in my opinion
Edit.
also, its always the Dragon Soul who is responsible for sealing the bore, but its...