Those four issues could've easily happened in one. What your describing in your first three paragraphs could easily be extrapolated from the first 2 pages of issue one of this series.
What really cracks me up is if you take a look at this story from the boiler plate perspective, it's entirely House of M, structurally.
And if you want to say that is a great reason to criticize this story, I will not argue that point. While all stories are derivative, this one certainly mirrors the structure of something Bendis wrote previously for Marvel.
But that being said, this series, IMO, has been done properly, as far as pacing was concerned. Because this was never going to be about somebody punching Ultron, the fight ending, and the next thing we see is Poker Night at Avengers Mansion.
It was NEVER going to be that way, because for whatever reason that made sense back in the day, Marvel established that Ultron was damn near unbeatable, especially when he got the adamantium body and ability to evolve. This story had to be written, at some point, because 35 years ago, Marvel established that there was simply no way that Ultron wasn't going to kill us all. Bendis hasn't reinvented the wheel, here -- I remember asking myself multiple times as a kid, "Why the hell would somebody build something like Ultron?"
That's why I give Bendis the latitude to tell this story -- in many ways, he's offering service to, what, a dozen or so stories that have been established about Ultron over decades. He's showing the end of mankind as we know it.
Wolverine's a killer. But to get to the point where he murders a hero who had yet to do anything wrong...that is a powerful story. What Wolverine did...it's horrible. But at the same time, it was necessary -- Ultron had killed us all! Yeah, there might be fates worse than death, but if you're dead, you have nothing to compare it to, right?
That's why this story...I like this series. As Victorian Squid said, that's fairly clear.
But that's because it's not as simple as punching Ultron or talking to Hank Pym -- the consequences of what Hank Pym did years ago...they mattered! It all mattered! We should be glad that Marvel told this story, because again, whereas DC just threw all their shit out and left every reader who read anything in the past out in the cold, Marvel at least respected their history and told a story that matters that is pulled directly from stories that we've read.