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!
I fully support this request.
On Helldive difficulty, the Assassination Target could be a group of High Profile units (e.g. for Cyborgs it could be 2 Warlords and one IFV).
I want this suggestion too, with a group of Assassination targets! 
(I don’t think that weighs in on likeliness of it happening or not though…)
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.
Nice ideas. Big guy with escort would be easier to implement than developing a new enemy, devs might consider doing that.