BO1 HC sort of sucked because the respawn timer you had after each death. If you died a lot, the timer was only for a second or two but if you stayed alive longer than 3+ minutes, you'd have a timer of 30 seconds or some stupid number like that. That lead to more camping since people didn't want to wait in the respawn timer but it also penalized aggressive players who stayed alive.
BO2 is much better because they removed the respawn timer completely so it's just like Core TDM only you have no HUD and bullets kill in 2 shots as opposed to the 20+ it takes in Core when the connection isn't good.

For the most part people actually run around and kill now.
Most of the time I'll run Ghost, Scavenger/Cold Blooded, and Dexterity. Ghost is for the UAV spam since people can't play without their HUD. Scavenger is just a precaution if you stay alive long enough since you can't see your ammo count...would hate to be 15-0 and then die because you fired and didn't have any bullets left.

Dexterity is for the fast reactions, it helps if you ADS for every kill like I do. Cold Blooded is just for that split second where an enemy doesn't see my name pop up, they think I'm a teammate until I shoot them. And Target finder campers.
EMP nade and spam them when you get a new scavenger pack...since you don't have Flak or Engineer, you can't see claymores and those will kill you. Shock Charges you can hear no problem and betties you can dodge no problem.