Chitauri were dropping hundreds of feet off buildings and denting cars when they landed perfectly fine and ultron drones were crawling up from underground shredding concrete with ease.
Clint and Nat engaged them constantly in close quarters. There was a time where Hawkeye for whatever crazy ass reason even tossed his bow away and took on a bot or two with just his arrows. These two have just faced tougher competition in my eyes. In terms of ward and may..There is nothing the watchmen crew have done I can't see them accomplishing.
And that's just h2h views..
Basic equipment, Clint can potentially solo.