If fans had their way, Black Widow would be the next solo Avengers film.
According to a poll that Fandango conducted on behalf of USA Today, which polled more than 1000 people who have already purchased Captain America: Civil War tickets, the clear favorite for a standalone Avengers film is Widow. She commanded 48% of the vote, followed by a distant 15% from Vision. Falcon brought in 12%, Hawkeye 10%, War Machine 8%, and Scarlet Witch 7%.
Black Widow has long been rumored for either a TV series or a solo venture, but there doesn't seem to be a better time to give her the spotlight then now. She holds her own no matter who you pair her with, and you can fit her into any type of story. Hopefully, this will actually come to fruition sooner than later.