For the 75th Anniversary of Captain America, Nick Spencer got to helm a massive crossover event that ultimately restored Steve Rogers to the role of Captain America. Of course, as with any massive crossover, it had multiple tie-ins, all of which are collected here and vary in quality.
Welcome To Pleasant Hill Prologue #1, Assault on Pleasant Hill Alpha #1, Assault on Pleasant Hill Omega #1, Captain America: Sam Wilson #7-8
These issues constitute the majority of the storyline, with the bulk of the actual story beats taking place here. The idea of Pleasant Hill is pretty solid - using a sentient Cosmic Cube in the shape of a little girl named Kobik, SHIELD have been brainwashing villains and placing them in a suburban town where they can live out their lives without murdering people. Of course, it all goes wrong when Baron Zemo recovers from his brainwashing and sets out to destroy Pleasant Hill from the inside. If you didn't read any of the tie-ins, these issues are the main ones you should bother reading. They're also the best in terms of artwork, with Mark Bagley, Daniel Acuna, and Angel Unzueta drawing them all.
Agents of SHIELD #3-4
Sigh. This is how not to do tie-ins. Standoff barely factors into these two issues, and they actually re-tell half a storyline that reappears in New Avengers later in the volume, word for word. The art is fairly bog-standard, if inoffensive from German Peralta, but these are tie-ins in name only, and will likely make no sense without the context of the other issues of the series.
Uncanny Avengers #7-8, All-New All-Different Avengers #7-8
These four issues are more of a mini-arc within Standoff itself as the two teams are drawn to Pleasant Hill by mysterious twin Maria Hills, and find themselves under Kobik's influence and assimilated into Pleasant Hill itself. This ends a little too quick, as if they're mostly just being forced into Standoff by editorial mandate. Oh, wait. Still, solid if unremarkable, especially for such good writers as Mark Waid and Gerry Duggan.
New Avengers #8-10
This, like Agents of SHIELD, barely ties into Standoff, instead stealing away the Whisperer character and trying to protect him. It also deals with another storyline that has been bubbling for a while in the pages of its own series as SHIELD takes on the New Avengers, leading to a battle between the American Kaiju (think patriotic Godzilla) and a giant Avengers Megazord. You can't make this stuff up. It's excellent storytelling, but again is barely Standoff related. It should make you want to go read New Avengers though, because that's awesome.
Illuminati #6
This issue looks more at the fall-out of Pleasant Hill than the actual goings on, as Absorbing Man deals with the fact he fell in love with another character instead of his wife Titania. I expect this plays out better in the main series, so this little snippet doesn't really work on its own. Some nice sketchy art from Mike Henderson though.
Howling Commandos of SHIELD #6
Howling Commandos as a concept should be great; SHIELD-sanctioned monsters fighting other supernatural threats. Instead, it was kind of a non-starter of a series with the blandest #1 I'd read in a while, so I didn't bother reading the rest, despite the potential. The fact that this issue is both a Standoff tie-in and the finale of the series means it has a lot to do in terms of story, tying in and wrapping up at the same time. The focus on Orrgo is different, but it's an ultimately unsatisfying issue since you're not invested in any of the characters reading just one issue, and knowing that the cliffhanger ending is never followed up just leaves a bad taste in your mouth.
So Standoff is, of course, a mixed bag. The Standoff story itself is great, but some of the tie-ins are poor or unnecessary. Your mileage may vary.
Oh! Standoff does resurrect the original Thunderbolts concept however, so that's a point in its favour.