It seemed to me that The Bourne Legacy was a transition film. It dug deeper into what had been presented in the three previous movies of the franchise, added new characters, and set up future story lines. Hence the story took a little time to develop unlike the other three movies which put the peddle to the metal right from the start.
Renner was great as Aaron Cross. I liked that Cross had a little sense of humor and wasn't a carbon copy of the Jason Bourne character. Bourne barely talks, whereas Cross had dialogue and seemed to have a slightly different skill set to Bourne. He got into the program with and under performing IQ score and needs the meds the program provides as much for confidence as to the actual enhancements they provide.
Wietz was also great in her role. Her character provides a very interesting partner in crime to Renner's Cross.
I found the movie very engaging. The storyline may not be as fascinating as Jason Bourne's where he has to figure out who he is and what the program he is involved in is all about. We know all this from his storyline. The story of Aaron Cross is different, yet I found it a lot of fun because it parallels the timeline of Bourne's. Never in film have I seen a sequel/prequel (not really what this movie is but for lack of a better term) where the timeline runs alongside that of preceding films. If rumor is true that Damon will reprise his role in perhaps the next film to join Cross, then I think The Bourne Legacy has successfully continued the story.
I had high hopes for the film and I really enjoyed it. I'd like to give the franchise a longer leash than a lot of critics have and see what the next film is like and how Legacy fits into the broader scheme of the entire story. I say give this one a go. Rating 8 of 10 stars.