The more I think about it, the more I like this movie. It's not as incredible as the first one, but having seen it so many times, it's nice to skip all the team origin story and jump right into things. See where it goes from here, if you will.
Also, I wasn't alive yet when The Empire Strikes Back came out, but I imagine a bit of a similar situation there. I know my parents were pissed at how cliffhanger-y that one was. Empires is often described as the darkest of the trilogy, which is good, and true... and yet when I draw comparisons to AoU, I sometimes wonder why that is. Obi-wan died in the original Star Wars - there were no deaths in Empires. Han gets frozen, but immediately after they say "he's alive" and he gets saved within 30 minutes of Return of the Jedi.
I guess you could say that Empires had the feeling that anyone could die (even Luke, who nearly bought it when facing Vader), whereas that's not quite the case in these Marvel films. But Quicksilver does die, and 4 of the 6 original Avengers seem to have left the team. That may prove to be about as permanent as Han's imprisonment, but at least it's something.
I guess it all depends on the state of things during Civil War - if Age of Ultron seems to have had no repercussions, then perhaps we'll look back on this one and say "it was cool, but not a lot happened." But if we don't see Iron Man, Cap, Hulk and Hawkeye fighting together again for a long time, maybe we will look back and say "man, the Avengers as we know them ended with this film." And that's kind of cool.
As someone who is just eating up everything Marvel puts out, I think this was a really solid movie. A lot of moving parts. Here's hoping Ant-Man can keep the trend going.