But in general, the theme of apathetic universe is what it was supposed to be, right?
Yeah, in Lovecraft's stories. An apathethic universe, and human beings living in an ever-decaying civilization that is all that keeps them shielded from the chaos and the madness. Thus, Lovecraft stories always end either badly or very badly, and his characters tend to kill themselves to spare themselves the horror.
Not so Derleth. He saw it as a regular good vs evil theme. So his take kind of rapes the original. Besides, it constraints the story
For the record, I do prefer Lovecraft. I do think he is being hyped. Sometime in the last few years the internet memetics took hold of this much neglected writer, and now we have the adjetive "lovecraftian" popping up every now and then, and people drooling about anything which vaguely attempts to emulate him. Take the goddamn "Zalgo" meme in /b/. Most of it sucks, but nonetheless people follow it because it's "lovecraftian". And thus, just like Anne Rice (and later Stephanie Meyer) ruined vampires, and just like all those "zombie" movies and books ruined zombies, the lovecraft-wannabes are abusing the theme.
Nevertheless, despite the hype, Lovecraft remains an influence in the horror genre, and often horror novels, or movies, or videogames do benefit from subtle homages. The key is in keeping them subtle (if possible) and of quality.