Correct!
Clue #1: Atlas, Rise! -
Atlas Shrugged was written by Ayn Rand, who inspired (to some extent) the Rush album
2112. "Isle of Avalon" is considered to be Maiden's Rush-iest song.
Clue #2: Sirens - "You're approaching the
island of the sirens." ~Savatage
Clue #3: Iron Maiden - "Nineteen
maidens, guardians of the Otherworld..."
Clue #4: King In Crimson - King > King Arthur
or Bruce wrote another "king" song ("Return of the King") which actually dealt with Arthur.
Clue #5: Isle of Avalon - Yeah... I literally gave you the subject matter straight up front.
Clue #6: @KidInTheDark666 - It's his custom title.
Clue #7: A Tyranny Of Souls - "When shall we three meet again?" > "When shall we meet again?" is likely a question one would ask that who ascends to Avalon.
Clue #8: Rob from the rich to give to the poor. - Reference to Robin Hood. Howard Pyle wrote about both Robin Hood and King Arthur.
Clue #9: Big D - A pile-driving barge that worked on building the Chesapeake Bay Bridge & Tunnel. Reference: pile > Pyle.
Clue #10:
Ooh, that was a good guess, but no.
Iron Maiden was a clue, and he guessed the actual song. Likewise, Isle of Avalon was a clue, and the answer was the actual song.
Clue #11: Cain. - Gave God an offering of
fruit. "The fruit of her body laden..."
Clue #12: The reason Our Father 'twasn't happy with him above. - Cain didn't give up his fruit in reverence to God, but in pride or something like that, hence why God was disgruntled with him.
Clue #13: To understand the third... 5x-1=3x+7 - When x=4, the answer is 19. Going back to clue #3: "Nineteen maidens..."
Clue #14: Thomas & Friends (Season 5) - "Toby and the Flood" was an episode from that season. > "...are flowing and flooding the land..."