A Heavy Operative would probably be good at taking care of Light Operatives. If they disguise you can still spot them. And if you kill someone you can hack their corpse to get radar. I don't think there's an ability that stops you from showing up on an Operative's radar.
If you really want t be an anti-operative, then I agree with Mad Hatter, Heavy operatives on defense will give them a headache. All of their information gathering abilities, an immunity to disguises, the best weapons, high health, and movement isn't that important on defense.
I think that the optimal team will very often have two of each kit. One squad of four "lights" roaming the perimeter of the map; one squad of four "heavies" rolling right down the center of the map. The role of the "heavy" Operative would be entirely defensive: spotting enemy Operatives, spotting enemy mines, making Command Post more difficult to hack, and interrogating incapped/dead enemies for information (and there are likely to be more of these near the "heavy" group than the "light". Lots of helpful things a "heavy" Operative can do!
Therefore, one of my characters, very likely one of my first two characters, will have Operative as a secondary class. You don't need many Operative abilities to serve a "defensive" role.