I like short story arcs. My favorite all-time example is Amazing Spider-Man 31-33 by Stan Lee and Steve Ditko. It's the one where Spidey gets trapped under that huge machine in Doc Ock's underwater hideout.
I must also say that I do like longer arcs if they are built with a hint at a time like the first season of Heroes. It was slowly revealed throughout the season how everyone with "special abilities" was interconnected. That I like.
A legendary moment. Did you see little reference to it on the Spectacular Spider-Man cartoon?
I love those, I really like if they're crossovers too, like first half in one book, second half in another and then the little arc is done and was fun and hit by two different artists/writers but with the same story.
Yeah I love that too, not a Heroes fan but in other stuff, love it, I try to add it when I'm plotting because it always makes you want to revisit the past and try to see what you've been missing.