Counterpoint, Falcon and Black Widow are in it. Falcon is a regular guy with a fancy jetpack, and Black Widow is a regular woman with pistols and fancy tasers. Antman is for sure more useful then they are. Hawkeye... not so much but he's just as much a core avenger as Black Widow is. Hell even Dr Strange's librarian is in the movie.
Speaking of B characters, Warmachine is on the poster (looking about as convincing as the MECs in X-Com Enemy Within, good job Marvel graphics department) so I assume he gets a bigger role then paraplegic best friend.