Kate Bishop's superhero name is simply Hawkeye, and as the name implies, she has a fondness for both bows and Clint Barton the Avenger. While her comic incarnation has had various adventures with groups such as the Young Avengers, she really came to life in Matt Fraction's Hawkeye series, which paired her alongside Clint Barton in a variety of capers. Clint functions as kind of a mentor for her, but she witnesses his failures as a hero and human quite often, and helps to keep him on the straight and narrow.
So why does the MCU need another Hawkeye? She synthesizes some of the best elements of a variety of popular MCU characters. For instance, she has the impeccable aim of Hawkeye, the spunky attitude of Spider-Man, and the detective skills of Jessica Jones, as demonstrated when she helps take down Madame Masque and later opens up her own private investigation business. She also works well as a character who straddles multiple worlds, as she helps out heroes like the Avengers while maintaining a healthy degree of distrust in major organizations like S.H.I.E.L.D. In short, she is a young, badass, independent female hero, and the MCU could definitely use more of those.