Spoiler Below Hey now. Hey. Hey. Everyone knows the Wasp sucks, but if you've read the Ultimates (pick it up - even if you don't like the idea of a black Nick Fury, it's a good introduction to the Ultimate universe) you know they've turned Hawkeye into Bulls-eye on steroids.
It's not a matter of everybody fighting the same supervillain - that's ridonculous. Nowadays they will actually go "Gee, dudes, it looks like Ultron here may be a wee bit dangerous for our good friends Captain America and Wasp to try to fight! Let's leave this to THOR, god of thunder and shatterer of worlds!" They actually put members of the teams up against threats that coincide with how capable of dealing with that threat they are - that's why threats in "The Ultimates" are so multi-faceted, like invading armies that need to be hit on multiple front, with the really powerful members actually fighting head-on, serving as a distraction while the likes of Cap go around and kick the asses of whatever asses need kicking behind the scenes.
...Actually, have you read "The Ultimates"? You can pick up the first two volumes, which are a great read, in trade paperback for fairly cheap. I highly recommend it, it's easily the best thing to come out of that continuity.