In no specific order:
"Night Gwen Stacy Died": Signature story that redefined the franchise going forward, claimed to have ended the so-called comic book Silver Age, has been revisited and adapted time and again.
"Kraven's Last Hunt": Signature story that's consistently on "best of" lists and elevated Kraven's reputation as a character.
Ultimate Spider-Man's "Power and Responsibility": Beyond being a well-written expansion of the origin story, it set up and sold the most influential run in the franchise's modern day. The USM series has been the source material for petty much every adaptation since it's publication (e.g. the stuff that influences the non-comics readers' perceptions of things) and it all started here.
Doctor Strange: "You are the right person to replace Logan."
X-23: "I know there are people who disapprove... Guys on the Internet mainly."
(All-New Wolverine #4)
I separate out Ultimate from 616 because they are different characters ( although both are Peter). A current story that I find exciting is Marvel Zombies. Stories ( and not just comics) that you have no idea who lives and dies work for me, so do “Cat and Mouse” type stories.
No Amazing Fantasy #15 in the Holy Trinity of Spider-Man comics? I'd go with that, The Night Gwen Stacy Died and Kraven's Last Hunt.
"reads that have shaped Spidey"
Ok, well I assume this means stories that would describe Spider-Man to a new reader and at the same time classic stories that give us long-time readers a gold standard for the character.
-Night Gwen Stacy Died
-KLH
-Kid Who Collected Spider-Man
To me those three reveal the heart and soul of why Spider-Man is an interesting character. I'd almost include Master Planner saga, except KLH is a more modern take on the same concept and more influential now, I think.
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