Not necessarily individual runs on titles but overall, what period of time would we think might be Marvel's high-water mark in terms of storytelling, art, etc.?

For me, I feel like it was the late 70s into the 80s. The new generation of writers and artists were expanding on the foundations Stan, Jack and Steve had laid down, new ideas were taking root, and some of the greatest stories the company had seen (or would see) were being told.

The Marvel of the early 80s definitely has a special place in my affections, and objectively I think there was an upswing in quality around then, but hard to say it eclipses that fertile period in the 60s.

For me, the much of the 70's was weaker on a lot of titles (although there was still some great stuff out there).

My vote goes for 1979 to around 1983 for another great period (when the 14 year old me was devouring the X-Men, DD, Avengers, Alpha Flight, FF, Iron Man...!)

Personally I love a lot of the  story arcs from the early seventies, kind of hit or miss mid seventies, then just adore '77 thru '80.

I literally stopped buying and reading comics one issue before JB started on X-Men.  I am still looking for his rather pricey first issue!

I can readily agree that Marvel was amazing in its earliest days--that multi-year debut of heroes and villains might only be rivaled by the explosion of superhero storytelling that followed the creation of Superman and then Batman.

I started reading comics in '72, around eight years old, and so I missed out on the early days. I caught up later but to me, when I started reading. Marvel was already post-Stan/post-Jack and, in retrospect, maybe feeling a sophomore slump by then. 

That said, catching up on the stories I missed confirms why Marvel caught on. It was so different from what came before, it really was a revolution.