Time for full disclosure. I know next to nothing about the Ant-Man comics that inspired the movie. I don't even recall reading an Ant-Man comic. I know the original Ant-Man in the comics is Hank Pym. I know that he was founding member of the Avengers. I also think he was a crime fighter with his wife The Wasp. I do not know if she died in the comic. I think Ant-Man became the Yellow Jacket for a time. I also know that he was replaced breifly by Scott Lang in the late 70's. Ant-Man can also control insects, and that eventually, having used the Pym particle for many years, his ability to become smaller and larger comes to him at will without the aid of the suit.
Just as other Marvel movies have tried to give the characters a very human backstory, Ant-Man tries to do this with Doctor Hank Pym (Michael Douglas) and his daughter Hope (Evangeline Lilly) by running a parallel story with Scott Lang and his young daughter. We also have a villain who, like most of the Marvel villains, is basically a psychopath. Darren Cross (Corey Stoll) becomes the The Yellowjacket that Ant-Man must stop. The stronger themes that I've noticed in Captain America, does not run strongly in Ant-Man. It is the basic good vesus evil theme.
What the movie does do is expand the Marvel movie universe in much the same way that Guardian's did. It seems more off-the cuff and irreverant than the Avenger films. It still has references to the Avengers and the evil Hydra, and it is clear that Ant-Man will become a member of the Avengers. Paul Rudd has already been signed for the up-coming Captain American: Civil War and the next two Avenger movies. Ant-Man is a fun and well-acted movie. It is worth the watch even if it suffers from the same over-use of CGI action sequences from which many other action movies also suffer. I liked it.