Yes. (He’s one of the Warriors Three, supporting characters for Thor. Volstagg is pretty much Shakespeare’s Falstaff, but with a good heart).
Yes, with his “Flame On!” The lined face was the common stylization for the flames covering his face in the 70s, IIRC.
Yep. His forehead horns are kinda flat-looking, but they’re clearly visible.
The “vaguely wing shaped thing” is the wing on the left side of Cap’s cowl. You can see the left half of the “A” on its side near the top of the tree. It’s Cap’s left profile, looking straight up. When I blow it up, I can clearly make out his eye, maskline on his cheek, nose, mouth, and bits of his chin and cheek.
I agree with @Kamino_Neko, I think the berry bush has got to be Man-Thing. The area between the two symmetrical berries is really dark and blurry. Between 70s low-fi printing and jpg processing, I think we’ve lost the fine details that would have shown his features.
…
A lot of those faces are pretty crappy - they’re just their faces drawn onto the background. But a couple are genuinely clever. Volstagg flows into the landscape, but is still pretty easy to spot. But Howard the Duck and Impossible Man are both distinctive once you see them but well-hidden and actually use the terrain features. Assuming the berry bush is Man-Thing, that one is also kind of clever. Iron Man is easy to spot, but his face incorporates a number of gags.
Does anyone know if “Thorn Creek and Western” has any significance? The only thing I can come up with for naming the station “Benjamin” is a reference to Benjamin J. Grimm, but I don’t know why the Thing gets a special shout-out. Of course, those could be private in-jokes by the artist.