Man to Man
The basic level of engagement is man to man, and this is really the basic level of almost all RPGs. Weapons are human scaled in terms of damage and ability.
Parapsychics move to the top end of the man to man scale, as they are able to threaten vehicles and structures, but largely retain their human vulnerabilities.
Power Armor is also top end of the man to man scale, as power armor can carry heavy weapons, but is able to better resist damage.
Vehicle to Vehicle
The realm of most RTS and wargames, vehicle to vehicle generally focuses exclusively on combat. Weapons and damage are scaled to vehicles, and even the lightest weapons are able to instantly kill. Conversely, the majority of human scale weapons are not able to affect vehicles. This is generally speaking, as there are light vehicles such as automobiles and small aircraft that can be very destructible, and there are some infantry/man portable weapons that are able to do a lot of damage, such as the rocket propelled grenade, satchel charges, shoulder fired missiles, and the like.
Mecha are the largest and most powerful vehicles currently in use, and mix the technology of fighter aircraft with the versatility of the infantryman and the armor and durability of a tank.
Tanks are still in the fight, as their armor is impressive, and they can carry heavy amounts of firepower.
Fixed installations and fortresses typically are armed with vehicle scale weapons
Aircraft, fixed wing jet and rotor craft are also vehicle scale.
Ship to Ship
One of the levels in the Cosmic age is ship or capital scale combat. These are the biggest of the big guns and few vehicles can withstand a hit from the guns involved. Weight is less of a concern so when a gun calibre matches a vehicle round, the capital weapon is firing a longer heavier shell.
Surface Naval Warships fire guns that measure in inches instead of millimeters or calibre. They also carry heavy missiles, and in the cosmic era can mount large powerful lasers, rail guns, and particle cannons.
Submarines, less directly armed, are also in this weapon range.
Space Warships are the same as surface warships, minus ballistic guns. They are also much more likely to have energy weapons.
Computer to Computer
cyber warfare is very much different in the Cosmic Era. Given the nature of the Cognitive Network and either borderline sentient or completely sentient computers, cyber warfare can move and flow more like actual combat with rival machines and operators working to destroy the rival. While there aren't blazing guns and lasers, and the pace is most of the time much more like submarine warfare (stealth rather than firepower) and theft and sabotage over collateral damage.
AISCs are the big dogs, veritable gods in the CogNet, since they control it's very existence. Their subordinate computers, the LAISCs and AIs are their avatars and champions.
LAI and SI are the main encounters, along with other human users.
There are servant and protocol programs and constructs that function as tools, weapons, and pets.
Stub: submitted to write a basic idea down. Unfortunately, this doesn't really add anything of value or anything particularly new.