^^^ Cool theory.
Mine is probably more well-known, but I discovered it nonetheless and thought it fascinating.
When the last Dragonborn travels throughout Skyrim, assassins from the Dark Brotherhood are sent their way. Despite the fact that they all carry letters, none of them say who desired to kill the Dovahkiin.
I used to accept this as a simple fact of the game, put in to either introduce people new to TES to the Dark Brotherhood or as a simple, random encounter, or perhaps as a message from Bethesda that the Dragonborn was not liked by everyone.
That is, until I made a thief character, who obviously joined the Guild down in Riften.
Now, as someone who has sunk major hours into Skyrim, and as a self-proclaimed Elder Scrolls nerd, I was instantly drawn to the Shadowmarks the Guild uses, and quickly learnt their meaning.
One night, Daro'Shulya, my thief, was just trolling through Riften trying to steal herself some swag, until she came across a large mansion with the Shadowmark 'protected' on it. I walked to the door, to see who's house it was- and it was Maven Black-Briars. Well, Guild members had told me to never steal from her (she's important blah blah blah), but that, combined with the Shadowmark and the fact that I have always DETESTED Maven, just made me want to break in.
So long story short, I did exactly that. I stole everything I could from that house, just to spite an AI character who won't even notice, and then I arrived down in the basement. I instantly see a door which is locked with an Expert-level lock. I pick it and- OHHH SH*T A BLACK SACRAMENT!
Looking further, I find notes from her to the Dark Brotherhood expressing dissapointement that they had not been able to kill the target she had given them.
And I may believe that that target is the Dragonborn only because I hate her, but c'mon:
-She knows EVERYTHING that happens in Skyrim. She probably heard about the prisoner who escaped Helgen the very same day, and she obviously would hear about you killing the dragon at Whiterun.
-She is power hungry and may believe the Dragonborn would claim more power in Skyrim than she could get
-I mean, WHO ELSE could fight off so many assassins besides the Dovahkiin?
-Seriously, is there anyone else in the whole province who can fight off a Dark Brotherhood assassin, especially someone who Maven knows
-She's also a biiiiitch and would want to kill us just for the sake of it
(okay that last point is just me being salty)
(also i'm pretty sure that the assassins come after you even if you don't complete dragon rising but idgaf and also maybe she has a premonition that the prisoner who survived helgen has potential. and even if your character doesn't do dragon rising i'm sure they do plenty of other important things in skyrim and that is probably enough for maven)