Stabby Joe said:
The darker suit though? The Avengers-universe had more colour than most other comic films up to this point.
I hope Coulson makes some form of an appearance, he's his biggest fan.
The darker suit is about function over form. He's no longer the solider/propaganda tool that he was during world war 2. He's a tactical soldier that requires stealth. It's more uniform than "blazing symbol of patriotism to inspire pride." The world has changed, and that's likely one of the themes on which the movie will touch. The in your face, "American and proud," our government is bigger than yours, attitude is no longer chic. It's about espionage now.
Would you tell soldiers going into battle that they need to lose their camouflage uniforms and switch to uniforms that prominently feature the colors of their nation's flags because "patriotism?" The purpose of the uniform in Avengers (designed in part by Coulson) was because Captain America needed to be a overt symbol in the eyes of the people while taking on Loki (and company). That's not longer the case. Cap's no longer a flag to be paraded around. He's a scalpel used surgically.
Also, I'm betting that the uniform will be a part of his arc: he adopts SHIELDs uniform and their cause, giving them the benefit of the doubt. He'll probably return to his original uniform when he accepts that SHIELD is about ruling with fear as opposed to governing with freedom. Adopting his original uniform would be symbolic of him casting off SHIELD's belief and displaying his own proudly. I wouldn't be surprised if Falcon's costume starts out the same way - SHIELD issued black/blue. Then he becomes a soaring (figuratively and literally), "flamboyant" symbol freedom and "rising above," wearing his more traditional red costume by the end.