I found an excellent and really insightful interview with the screenwriters of Cap 2 Christopher Markus & Stephen McFeely by Steve Weintraub at Collider (who's does great interviews!)
http://collider.com/captain-america-...dier-spoilers/
It's 15 minutes long and they basically just talk about how smoothly the production went, there was no problems with the script, hardly any changes etc which sounds great (unlike Thor 2 which had quite a few production problems).
Overall, it's really insightful, they mention that the third act with the Helicarriers came from an idea that both they and Kevin Feige had and it comes from The Ultimates 2 comic with Helicarriers falling near the Triskellion and Kevin thought it looked cool. Also, they mention that the causeway scene was meant to take place on a causeway above water with a draw bridge, but they couldn't find one to shut down to film, so they done it on the streets instead which worked out better.They also talk about the Nick Fury chase scene and how they wanted to give him a proper action scene, the Stan Lee cameo, the Peggy Carter scene and the fact that they played with adding more flashbacks in early drafts of the script, but some felt unnecessary. Really good watch!
EDIT: There is also another another interview from Steve Weintraub at Collider, but this time with Anthony & Joe Russo which is also 15 minutes long.
http://collider.com/anthony-joe-russ...ier-interview/
This interview is also very insightful, they talk a lot about Robert Redford's character arc, they mention that there will be about 5 minutes of deleted scenes and talk about one with Black Widow and Nick Fury. They talk about the logic of Fury's other eye under the eye patch, the Arnim Zola scene and the fact that it is slightly more science fiction than the rest of the film, but they liked the fact that the scene was slightly weird, but that was probably the scene they struggled with the most with the exposition etc so this interview is another great watch!