Big Avengers fan, though not currently reading it. Things have changed too much for my liking.
After the original 402 issue run (volume 1) there was this stupid concept called Heroes Reborn in which The Avengers were liefeld/image-ized with dumb stories and lame new costumes for 13 issues (volume 2). Then with Heroes Return (volume 3) Kurt Busiek and George Perez set out on a nostalgic trip "70's style" with big teams, little character development and mostly forgettable villains that had already been beaten way too many times for it to matter anymore. Right now, some guy named Geoff Johns who is really working for DC comics is ruining The Avengers with lame Justice Society style stories.
If you really wanna get something Avengers where you dont need to collect the current run to know what's going on, just get the "Avengers Forever" 12 issue masterpiece by Kurt Busiek & Carlos Pacheco which is also available as a TPB. That series takes place outside of continuity and the only thing you need is knowledge of the early stories, mostly 60's/70's Avengers. That series would make an awesome movie!!!!!!!!!!!