matic22
Ancient Mariner
And if I remember correctly, Bruce has said that, basically, Steve's only contribution to the Maiden song was naming it "The Wicker Man" (and perhaps doing a bit of arranging), meaning that Adrian probably wrote the music and Bruce the lyrics (I'll see if I can find a source for it).
So, with a different title, it sounds pretty likely it would've featured on a third Bruce-album in an alternate timeline
Well Wicker Man for me was always some kind of Road To Hell part II musically.