And you substituted one humanoid for another? Cause apparently, being humanoid in all ways except for a mouth and a nose makes you more cosmic.
What's insulting about that? Galactus isn't just some random alien. He's a force of nature unlike anything any human (or any alien) has laid eyes on. As you can see from the scans you quoted,
every alien race sees something different when they look at Galactus. It's not as if it's a failing unique to humans. That's because Galactus isn't a flesh and blood being, but something else. Something which normal mortal minds can't process, and so each mind perceives that being as something they can understand. Didn't you want something
alien? How much more alien can you get than that?
"I don't claim to know anything about Galactus."
That's pretty clear, otherwise you wouldn't have made a statement like that.
1) Silver Surfer is a member of a race called Zenn-Lavians, and as it so happens, they're identical to humans.
2) That silver skin he's covered with isn't a natural trait of their species. It's part of the powers that Galactus gave him, just like how Colossus' organic steel skin isn't a normal human trait, but rather a power particular to him.
3) The Silver Surfer is just a regular guy with superpowers. Galactus, on the other hand, is an incomprehensible force of nature. That's why the Surfer always looks the same while Galactus looks different to people. They're certainly not anywhere near being the same sort of creature. The fact that Galactus is at least 20 times the Silver Surfer's size should've been your first hint.