I was able to enjoy it as a stand-alone movie. I know a lot of people are saying "What about the other Avengers? What about Shield?" I thought about it, but it didn't bother me that much. I wanted to see how Tony was going to use his wits to handle this seemingly unbeatable bad guy.
I think this will be a problem for all future Marvel movies. The Avengers set the bar sooo high, that expectations are crazy.
It's amazing that they can kill off so many characters and still have so many left to work with! If you haven't seen it yet, you owe it to yourself to check out the ONLINE ONLY EPILOGUE, thankfully crossposted to the [as] YOUTUBERY: