Haha, I must've made that same exact argument a dozen times on the Marvel Ultimate Alliance forums whenever someone suggests that Clint should be in the game as Ronin, not Hawkeye. And it's true. Not only are there a lot of martial artists and swordsman in Marvel but by comparison Clint as Ronin would look mediocre next to them. Clint has admitted in the past that when it comes to martial arts technique Bobbi outranks him and in Reunion she easily out-dueled him in the bo-staff which puts him as Ronin below her skill level. And not to disrespect Bobbi's skill because she is good but she's not Elektra good.
Compare that to Clint as Hawkeye being able to beat heavy hitters like She-Hulk and Abomination by himself and it's a no brainer which persona is better (for Clint).