I reakon that in Halo 4, assassinations should be included but refined so that an assassination cutscene would be different for each weapon, like how in Halo: Reach, the energy sword had a different assassination to the regular ones.
For Example:
The Spartan Laser: Your character smashes the victim in the back making him fall to the ground and then melts his head by charging the laser and shooting his head.
Maybe a little less violent than that, but i think it would be kick-ass if each weapon had its own unique assassination move, kinda like Gears of War 2 & 3.
