@RohanDandavate - I would -like- to someday? The problem is that I've become a well enough known author with my original works that I always have the fear of copyright challenge lurking around the corner. If Marvel ever comes to me about my fanfiction and says "Mine ... pull it down," I'd just pull it down ... it's their universe, their characters, I was just playing in their sandbox. But usually when playing in their sandbox, I get ideas for my OWN original characters who I then transplant into my OWN original universe. For example ... the Chitari kids at the end of the story. If I was to call those kids something else, and write about about a race of shape-shifting fairies, would Marvel come looking to shut down my universe because the original idea came out of a fanfiction? In this case I could likely prove it was too much of a departure from the original work for them to be able to latch onto, but in the meantime, I would spend hundreds of thousands of dollars in legal fees to fend them off, would lose the ability to publish any story in that universe, and those stories would forever have the stigma of 'she must have stolen it from Marvel' (even though they are clearly original) because of where I got the idea.
I didn't worry when Marvel was owned by Marvel, but with Disney now owning them, the sue-happy corporation which is notorious for it's viscous overreach (we have a saying in the legal profession, 'Don't Mess with the Mouse), it's made me wary of playing in the Marvel sandbox anymore.