Re: More of a letdown - Galactus or Parallax?
Parallax actually had some story/exploration behind it, and was more or less an improvement over the cosmic space bug.
Galactus is the bigger disappointment, as his story elements were kind of set aside in favor of The Silver Surfer, but I can't pretend that the "cloud", as people call it, wasn't still kind of daunting and threatening. There was clearly something in there...we just didn't get to see it (well, most of it).
The main issue with the portrayal of Galactus is that he didn't really have a personality to speak of. It was just an event that consumed planets. In grand fashion, mind you, but there was no "I must survive" element to the concept as I recall...which was always what made Galactus interesting. You kind of didn't want him to perish, even if it meant eating a planet or two.
Writer and Lyricist of GOTHAM'S KNIGHT: THE BATMAN MUSICAL
And if I'm right
The future's looking bright
A symbol in the skies at night