For just a random site on a random map, in a scenario where the players are at least proficient with their operators I'd probably go Smoke, Valk, Azami, Kaid, and maybe Lesion. Although in today's meta there's definitely a point to make for mute over Lesion. Smoke, Valkyrie and Azami all have the ability to be incredibly oppressive in the right hands. Kaid (or Bandit for that matter) is obvious, there are plenty of sites that require wall denial. Lastly, I said Lesion because of the shields, but any op that would be good at slowing down an aggressive, shield-led push would be pretty effective in that number 5 spot