That said, Olivier Coipel's brief run a few years ago was probably the best the Avengers have ever looked. Take off the nostalgia goggles and see if I'm not right.

I was going to say "already-established characters" and also mention that Kirby didn't get to really let loose and establish the look-and-feel of the series the way that other artists mentioned in this thread did. Look at all the hallmarks that John Buscema provided-- Ultron, The Vision, Arkon, the early Quinjets, Yellowjacket, Wasp's outfit-of-the-week. Kirby gave us Baron Zemo, the Space Phantom and Kang. His most long-lived Avengers contribution was arguably Jarvis, and that was from Tales of Suspense.

That's not a slam of Jack Kirby, just a realization that he was more creative elsewhere.

For all the later artists, Perez wins out. Honorable mention to Byrne, Ordway, Milgrom, Epting (the only bright spot on a very long run of Bob Harras scripted stories), and Paul Ryan who really should get more love from fans than he does.

IF we're including West Coast Avengers, Dave Ross deserves an honorable mention also.

There were other great artists (all of whom have been mentioned, I think), like Buscema, Byrne, Epting.

(Paul Ryan? Seriously?)

On the flipside, while I know that they were fine artists elsewhere, Bob Brown and George Tuska were my least favorite artists on the title.

Kirby created the book and brought back Captain America, but I don't put his Avengers on the same level as his FF, Cap, Thor, or New Gods. It was still very good super-hero comics, of course. Neal Adams is the best Avengers artist who didn't draw enough Avengers comics to really count as "regular," and Alan Davis is a close second.

I also was a big fan of Steve Epting's run, and even though it was only a shadow of his quality which he produces today, you could still see the work was strong.
It only suffered due to it's (perhaps mandated) similarity to Image stuff.

Byrne's work on the title (not West Coast) was beautiful, classic Byrne, and some of the best work on the title by anyone. However, at the time, ANYTHING Byrne worked on had that level of quality. It's just that he gave a fantastic flair to the characters.

John Buscema's work was iconic.
No way around it.
He truly gave the Avengers their overall template.
His later work on the title, however, looked a bit rough (inker perhaps?) but still maintained the quality of bombast that he was called to the plate to deliver.

Those are my top 4.
If I HAD to choose only ONE... it would have to be DON HECK.
But only because the old-time look that was present in those issues deeply resonates with me.

I'll give 2nd place to John Byrne's issues.
His work back then was a hallmark of Marvel comics and the bar which I looked at all other art of the time.

~P~
P-TOR