Sure it was cool to see Spider-Man on screen, but Captain America: Civil War had no long lasting ramifications, at least in my view. We all know every Marvel movie ends with the good guys winning (beating the same villain), and we all know the Avengers will re-team against Thanos for Avengers: Infinity War.
For whatever reason, Kevin Feige and the Russo's decided against killing Captain America, but here they attempt to explain their reasoning (via Hit Fix):
Anthony Russo: We never talked about killing Cap in this one, right? no.
Joe Russo: We did for a beat. We talk about everything.
Anthony Russo: I think the thing to remember is, we do talk about every possible scenario over and over and over again for months and months and months. We talked about it. But it never made its way into a realistic outline.
Feige: Well, the ending was always more about fracturing the team completely before getting into Infinity War.
Joe Russo: We talked about lots of potential characters dying at the end of the movie. And we thought that it would undercut what is really the rich tension of the movie, which is this is Kramer vs Kramer. It’s about a divorce. If somebody dies, it would create empathy, which would change and allow for repair, and we didn’t want to do that.
Feige: In the amazing comic book story, which certainly the conceit of this movie is based on and some of the specifics — during their big battle, which has a hundred times as many characters, a character dies. And we talked about that for a while. And, ultimately, we thought what happened to Rhodey would be enough of a downer.
Anthony Russo: The tragedy is the family falls apart. Not that the family falls apart and then somebody dies.
I don't think their arguments hold up very well as we did see Rhodey walking at the end of the movie, which we are to assume means he'll be alright. Regarding fracturing the Avengers completely, even Feige mentions it leads into Avengers: Infinity War, but again, won't they just be reunited against Thanos? And Anthony Russo mentioning how the family falls part is a bit much as Thor and the Hulk weren't a part of Captain America: Civil War -- with Scarlet Witch, Vision, and Ant-Man just being introduced a movie prior, and Spider-Man and Black Panther being completely new.
Personally, I think Marvel blew it going the Civil War route instead of giving us another Captain America movie like the excellent Winter Soldier flick, or at least they blew it by not killing Captain America off like in the comics. Marvel only went with Captain America: Civil War (Avengers vs Avengers) as a result of WB announcing Batman Vs. Superman, and I think Marvel playing follow the leader here shows in the film.