I’ve noticed that assassination objectives dont appear on the highest level of difficulty. In fact, I had forgotten they were in the game.
However, I would love if my team was tasked with finding and eliminating a fully armored high profile cyborg with above average power and toughness in addition to the usual objectives found during a Helldive!
The group-assassination thing is a good idea.
Have some smaller enemies guarding a bigger, high-value enemy.
It would be like a convoy escort except for on the enemy side.