Now, I am not sure about what Variations of UNSC soldier there are; however, I do know that Cerberus has a wide range of troop classes that may give them flexibility on the battle field. Did my best to find them all. (Mostly from mass effect 3 and Mass Effect: Infiltrator)
Assault Captains: Cerberus officers leading squads of Assault Troopers into battle.
Assault captains have considerable health and possess a strong layer of shielding. Their shielding will regenerate over time.
Assault Captains will often take cover during the firefight, and tend not to come out unless you're in their line of sight. This allows you to wait out behind cover for your powers to recharge without being disturbed. If necessary, using Pull will flush them out of cover.Like regular assault troopers, assault captains possess jetpacks, allowing them to quickly get into the effective range of their Eviscerator shotguns. While they're in flight, using Pull can interrupt them.
Assault Troopers: (Variant 1) Standard infantry that form the bulk of Cerberus forces.
Offensive
Assault Troopers are armed with M-25 Hornet submachine guns, as well as electrified batons for melee attacks. They can throw powerful (but slow to detonate) Frag Grenades to kill enemies or flush them out of cover. They can execute downed soldiers with a stomp to the head.
Defensive
Assault Troopers possess moderate health without any kind of shielding. They frequently take cover during combat and also perform combat rolls to evade conventional or power attacks.
Assault Trooper (variant 2): Elite Cerberus infantry equipped with assault rifles or shotguns.
Assault troopers have considerable health and possess a strong layer of shielding, which can regenerate over time and will often take cover during the firefight, and tend not to come out unless you're in their line of fire.
These assault troopers possess personal jetpacks and can use them to quickly arrive in range for their Eviscerator shotguns, or get behind you. While they're in flight, it is possible to interrupt them with Pull.
Centurions:(Variant 1) - Front-line tacticians that lead squads into battle.
Offensive
Centurions are equipped with M-96 Mattock assault rifles that are modified to fire smoke grenades. They're also equipped with Frag Grenades, which have low explosion radius but can instantly kill the player on harder difficulties. Finally, they can attack their enemies in melee with electrified batons, which are far more powerful than ones given to Assault Troopers.
Defensive
Centurions have moderate health and shielding: the latter regenerates over time, with the speed depending on the difficulty. They will frequently take cover during combat and they can perform combat rolls to avoid gunfire or projectile powers like Warp or Incinerate. Their smoke grenades can temporarily obstruct the player's line of sight and targeting.
Centurion:(Variant 2) Cerberus shock troops that lead regular trooper squads into firefights.
Centurions have considerable health and possess a strong layer of shielding over it. Their shielding will regenerate over time.
Centurions will often take cover during the firefight, and tend not to come out unless you're in their line of fire. It is recommended to take them out first due to the increased threat they represent.
Engineers: Cerberus technical personnel armed with shotguns.
Armament
-M-22 Eviscerator
-M-96 Mattock Auto
Because they lack the armor of mainline Cerberus soldiers, the engineers are particularly fragile, possessing low health with only a weak layer of shields on top. Like with other enemies, their shielding will regenerate over time.
Engineers are only dangerous at short range, and their relative fragility makes it easy to eliminate them before they become a threat. However, some of them are equipped with assault rifle and can shoot you while running.
Ogre Mechs: Advanced, durable Cerberus mechs armed with pulse rifles and laser cannons.
Ogre mech is a very durable enemy, with very high health, armour and shielding. Like with other enemies in the game, its shielding will regenerate over time. The Pulse rifle fires in multiple burstsThe Ogre mech must charge its beam attack.
Orcus Mechs: Standard mechs used for security purposes.
Orcus Mechs only possesses health and lacks shielding or armour of any kind. To compensate for this fragility, they're always released in large groups.They wield M-96 Mattock Autos, which prevents most rush tactics used on them.
Riot Troopers: Troops armed with shotguns and large, bullet-resistant riot shields for crowd control.
If the shield of the Riot Trooper takes enough damage it will break.
Riot Troopers will also lose their shield and armor if they are sent into the air with a biotic Pull or damaged by the biotic Storm.
Even when they're carrying shields, Riot Troopers can still be knocked off their feet with Slide. Use that to your advantage.
While they're still carrying their riot shields, Riot Troopers will not get into cover as there is no need for them to do so. This changes once they lose them one way or another.
Snipers: Troops equipped with sniper rifles and specialized in long-range engagements.
Snipers have low health and a weak layer of shielding on top of it, which will regenerate over time. This fragility is offset by their high damage output.Snipers will often sit behind cover, popping out only to take a shot.
Adjutant - Reaper creatures genetically engineered by Cerberus to serve as troops.
Offensive
Adjutants can fire a charged biotic projectile similar to a Singularity that, upon hitting something, floats in place for a certain amount of time. It damages and disorients targets within its field. At close range, Adjutants will charge and leap at targets, damaging and knocking them down, similar to Brutes.
Defensive
Adjutants have above average armor and barriers, and are fast opponents that can rapidly evade an attacker's line of sight.
Atlas - Slow, heavy, and durable mechs equipped with rocket launchers and cannons.
Offensive
The Atlas is equipped with a powerful rocket launcher which deals immediate damage and then a small amount of burn damage over time and a high-power mass accelerator cannon. At close-range, it can attack with its claw arm, either by way of a short krogan-style charge, slamming it into the ground, or by picking up its target, instantly killing it by crushing its midsection.
Defensive
The Atlas possesses extremely durable shields and armor, and can shoot smoke grenades. Its shoulders and crotch are protected by destructible armored plating.
Combat Engineer - Specialized support units that deploy Turrets.
Offensive
Combat Engineers are armed with a M-5 Phalanx Heavy Pistol, but their primary means of offense is deploying a powerful stationary Turret. They have no melee attack, solely relying on their M-5 Phalanx to kill their foes, even at point-blank range as a last resort.
Defensive
Combat Engineers have shields for extra protection and may evade attacks by rolling. Engineers can also repair the armor of their Turrets and Atlas mechs if they become damaged.
Dragoon - Armored combat specialists armed with biotic lashes for close to mid-range attacks.
Offensive
Cerberus Dragoons are equipped with the M-25 Hornet SMG and biotic lashes, which they can use to lunge toward the player or slam the ground with them for a circular melee attack. They can instantly kill downed players with a stomp execution.
Defensive
While they possess powerful armor, Dragoons are devoid of any shields or barriers whatsoever. Given their nature as an armored enemy, Dragoons cannot be grabbed over-cover for instant-kills. However, headshots will still deal 40% more damage.
Guardian - Fortified units equipped with highly-durable shields.
Offensive
Guardians are armed with the M-358 Talon pistol. They can also use their shields as an effective melee weapon if they get close enough. Guardians also carry electrical batons, much like the Centurions and Assault Troopers, but only use these when their shields are gone.
Defensive
Guardians are distinguished by the nearly impenetrable shields they carry. A few weapons and powers can stagger them. They almost always come in pairs, which helps mitigate flanking tactics and allows for them to cover each other and other Cerberus soldiers. Naturally, they have no way (and little need) to dodge player attacks with their shield up, but once rid of it they can evade attacks with combat rolls.
Nemesis - Sniper specialists that can inflict instant death on opponents.
Offensive
Nemeses are armed with a M-13 Raptor sniper rifle with a laser sight. Note, however, that it is much closer to the M-98 Widow or M-92 Mantis in terms of rate of fire and damage. Nemeses do a surprisingly large amount of damage, being able to instant-kill on Insanity.
Defensive
Nemeses are primarily protected by shields, but also rarely leave cover. They will target enemies at range, peeking out of cover only long enough to aim and fire a shot. Because they lack any form of short range offense, and their targeting laser gives away their position, they frequently run to a new position after a few shots to avoid attack; even using rocket propelled boots to escape to higher ground. If approached in close-range, they will attempt to run and find cover further away. They will occasionally perform combat rolls to dodge gunfire or projectile powers like Warp or Incinerate.
Phantom - Agile biotic units armed with a monomolecular blade and Palm Blaster.
Offensive
Phantoms are deadly in melee combat. They are armed with monomolecular blades that they use to deliver lethal strikes; a single direct stab from their swords can kill instantly. They also possess a powerful semi-automatic projectile-based weapon in their right gauntlet, from which they shoot kinetic-based projectiles with deadly accuracy from the palm. They slash their swords once or sometimes twice in quick succession, destroying shields and often health in very little time. Melee combat is strongly discouraged unless the Phantom's sword is broken.
Defensive
While they are protected by biotic barriers, Phantoms rely on their agility to evade enemy fire. They can quickly sidestep, roll, or leap away from attacks, disorienting the player. They can create a localized biotic barrier (shown as a energy field in the palm of the gun hand and a visible biotic "bubble" surrounding them), making them briefly immune to most powers that have a projectile component, and reducing damage from normal weapons. If endangered, Phantoms will also activate cloaks and take cover for a short period. They can recharge their barriers and (to a smaller degree) their health over time.
Rampart Mech - Heavily modified LOKI Mechs used to contain Omega's civilian population.
Offensive
Rampart Mechs are armed with a shotgun for mid-range target suppression and an omni-blade for melee fights. When destroyed, their remains discharge intense heat for a short period which can damage unwary opponents.
Defensive
Rampart Mechs are armored and relatively durable, but are programmed to rapidly close the distance with any targets and thus seek cover only infrequently compared to other enemies. At a distance, they can activate powerful shields that protect against long-range incoming fire, but prevent them from advancing.
