[Jason Abbadon]

I still think small crossovers can be really smart and well written- a perfect example being the recent one month crossover between Daredevil Spider-Man and Punisher.
That kind of crossover give readers the story from three very different perspectives and lets the characters develop their own book's plot/story lines while still behaving as they should.
For example, we've all seen stuff like Civil War where both Cap and Tony were acting NOTHING like their established character backgrounds or motivations would have them act- the editors decided to go with the story and all the writers had to bend their characters to fit that crossover- to the point where it seemed more like the Ultimates universe than the main marvel one.

The best crossovers are cosmic crossovers- mainly because it's not Earth-centric and the characters involved are not "headliners", but interesting, well written characters- not media "properties" like Wolverine or Spidey that you
A) know will never die and
B) cant do anything that changes their core character.

Superman will never screw the pooch like John Stewart did and get a planet full of people killed, changing him forever into a much more deliberate, guilt-ridden hardass guy.
Fans would not have it- they like constantcy and to be able to pick up certain books and know so and so is the best there is at what he does or the Dark KNight or whatthehellever.

Stick with small story-driven crossovers and skip the nonsense crossover issues of a title- they're always a waste of money- every two crappy filler issues is a Marvel Universe figure!
If you count the Fearless useless miniseries, Fear Itself had twelve filler issues! That's a Galactus, right there....and since the issues never go up in value, you could always get back issues if anything actually happened worth reading (certainly not in Bendis' Avengers!).