Big Name Fan: Of the FBI and J. Edgar Hoover in specific. Doubly ironic because at the time Hoover was investigating Elvis as a possible subversive.
Creator Backlash: Presley grew to hate the movies he was starring in (several sources such as the documentary This is Elvis suggest he even got physically ill from them at one point), and certainly you can scour Elvis' live performances from 1969 to 1977 and except for one or two exceptions that became regular parts of his act you'll find very few performances of movie songs from the post-1960 era.
Fan Nickname: The lesser-known "Elvis the Pelvis", among others.
Might've been used as a detractor nickname, too. Elvis notably disliked the nickname, saying something along the lines of "I can't fathom what sort of adult would come up with that" in an interview (which can be viewed in Graceland, Memphis, if you take a tour of the estate as it is).
What Could Have Been: Elvis never toured outside of the US, mainly because his manager, Colonel Tom Parker (real name: Andreas van Kuijk) was an illegal immigrant from the Netherlands and couldn't get a passport.
More like a case of Critical Research Failure on Parker's part: he had served in the US Army and was married to an American citizen. Parker could have applied for legal citizenship at any time based on either of those two factors. Maintaining his Dutch citizenship, however, did prove advantageous to him in avoiding legal trouble.
According to Parker's biographer, it's possible that he fled The Netherlands because of a Dark and Troubled Past and was fearful of having his true identity revealed.
Let's just say all of Elvis' film career is a WCHB. He demonstrated a great sense of humor and comedic timing that could have made him a big comedy star, but Parker killed any potential acting career.
It can't have helped that the Western Flaming Star, one of the few movies he made where music was on the backburner, was a box office disappointment (though considered one of his best screen turns).
When Sam Phillips decided to sell Elvis's contract in 1955, Atlantic Records entered into the bidding for him. Atlantic bid $30,000, but was outbid by RCA Victor who paid $40,000. Atlantic vice president Jerry Wexler loved Elvis's singing and bid aggressively, although he later admitted he didn't know how Atlantic could have raised the $30,000 if their offer had been accepted.