Stan Lee being a showman and huckster is why he became so wealthy. If wealthy is an accurate term. Since I don't really know what Stan's bank account looks like.

 If Jack Kirby didn't want what Stan offered that's fine. He is entitled to make that choice. But had he taken the job he would have gotten better pay and benefits as an employee of the company. 

But that is all a separate argument. Stan had no obligation to anyone other than himself. When it comes to securing success. 

But still he was the one responsible for giving credit to the artists and writers. 

It's sad really how people can say that Stan Lee stole credit from others. When it was Stan who began giving that credit in the first place. 

It seems strange to damn Stan for having the wisdom and confidence to lean so heavily on the talents of his artists.

Yes, the heavy lifting probably was done by Ditko and Kirby in terms of long hours spent at the drafting table, pacing the stories, carrying the load of the visual storytelling.... BUT many of the elements of that hard-to-define magic that separated Spider-Man and the FF from the crowd seem to stem from Stan. Yes, Challengers of the Unknown is superficially similar to the FF, but the title is also clearly inferior. Stan sprinkled the magic dust on the goodies that Ditko and Kirby hammered out.

As to the Lennon-McCartney analogy, Lennon-McCartney is largely an attribution of convenience, rather than a reflection of how the songs actually came together. The earlier stuff apart, most songs were largely written by Lennon or McCartney. I prefer a Rodgers/Hammerstein analogy myself  :).

The Screenwriter; Stan Lee 

Director; Jack Kirby, Steve Ditko, John Romita etc..

I will admit I don't know how well his DC work sold at the time. I seem to recall that most of the Fourth World stuff was cancelled at about 12 issues.

However, knowing that Kirby was an unending font of new characters and titles, he figured he was practically doing Kirby a favor getting him out of this corner he'd backed himself into, having to write Fourth World stuff and only Fourth World stuff. Cancel them all, and Kirby's free to be Kirby again, coming up with new books like Kamandi, the Demon, Sandman, Manhunter, Atlas, and so on, forever, filling the DC coffers with new (or sometimes reinvigorated) concepts and characters that have nothing to do with the worlds of New Genesis and Apokolips.

I agree that Infantino pulled the plug much too soon, but he was also the one who put Colletta on the books and ordered Murphy Anderson to redraw all the Superman character heads. Once he made the right decision to bring Kirby in, it seems he couldn't stop making wrong decisions to somehow mitigate and undo that initial coup...

And really, no one had ever been let off the editorial chain prior to this. The idea of simply letting Kirby be Kirby was likely unimaginable to the editors who naturally felt that everybody needs to be, y'know, edited!