Say what you will, you won't feel ripped off after reading "Hawkeye & Mockingbird" #4. Jim McCann and the Lopez Brothers pack in so much that the problem may be that there's just too much in the issue. McCann struggles to give every character a moment while advancing the plot significantly, causing the pacing to feel rushed and cramped. Even still, it's a fun, action-packed read that has a clear concept of what it is and what it's goals are.
The issue starts off in the middle of the action as Hawkeye, Mockingbird, and Dominic Fortune are buried under a pile of rubble in an explosion with at least one of them flatlining. But, that's just a tease as this is the issue where the heroes pull it together and begin to take the fight to the villains, the Phantom Rider (or his ghost as it possesses his granddaughter) and Crossfire. The explanation for this shift comes from the characters as Bobbi puts Clint in charge, seeing that she's too emotionally close to the situation to lead properly. Her willingness to do this goes a long way to bridging the gap between the two and pays off later in the issue prior to taking on the bad guys in a museum.
The museum fight is pretty goofy as Hawkeye hams it up with dinosaur bones, and the Lopez Brothers play to that side of things well, while also delivering some stunning action shots. Their thin line work is good at communicating speed and fitting a lot into a page. McCann demands a lot from them in the sequence and they deliver ably. The fight itself is only a couple of pages, but it seems bigger and more involved because of the art is so lively.
The pacing problem crops up towards the end where the tone of the issue suggests that this is the conclusion as the good guys get back at the bad guys, but, as the issue progresses, fewer and fewer pages are left. While McCann tries to set up a cliffhanger/lead-in to the next issue, it feels like the comic just ran out of room. The momentum is so strong that it's not a case of wanting to see what happens next, it seems structurally wrong to not have the rest of the story here.
The balance between plot and character is also problematic at times, but McCann keeps things from leaning too far in any direction by having the plot exist as a function of the characters. How they respond to things that crop up tells us a lot about them, like Dominic being annoyed that his injury keeps him sidelined or Hawkeye's strategy to take down the Phantom Rider and Crossfire. It's very effective storytelling.
Going into this issue, I'd heard a lot of great things about "Hawkeye & Mockingbird" and they're all true. McCann is writing a fun, character-driven book that throws in some great action scenes by the Lopez Brothers.