I'm not a fan at all of any of those Thanos Infinity series, but that is a pretty nice George Perez cover.
The John Byrne FF cover - couldn't make out the issue number - is that an homage to a cover or interior panel from an older comic? How about the Avengers one above it, with the giant green (Hulk?) hand?
It's #244 ... I always took it as a homage to Norrin Radd's birth into Silver Surfer, as that cover is Frankie Raye into Nova. I don't remember much else of the issue other than she did it for the same reason Norrin did for his homeworld.
It looks familiar but I can't put my finger on exactly what I think it's taken from - but it's probably the scene (in the Surfer series drawn by John Buscema?) that you mention, though I believe there's at least one other panel with the Surfer coming forth from Galactus's hand, this one in the Lee/Kirby Surfer graphic novel from the late 70s or early 80s . Maybe there's a bunch of them, for all I know.
I came very close to voting for that one myself. We see once again how effective a visual design Mysterio was, at least in the hands of a master artist like Romita, Sr or Ditko, even without a sight of the trademark dome. As we were talking about in some other thread a while ago, it's too bad the character himself doesn't quite live up to his visual image.
Wally Wood used a very similar design to great effect for a Dr. Doom antagonist in Astonishing Tales in the early 70s. I wonder if that character was ever made use of again.
There were several I really loved, this is probably my favorite theme so far with this game. I liked the classic horror ones the best, and choosing from that pile is still tough. I've decided on Phil Maurice after a second scroll through the pages.