The Hordes of the Things (HOTT) rules set defines units by troop types, reflecting not just the unit's weapons but also how the unit would be used on the battlefield. As I was adapting the HOTT combat rules, I would adopt a similar convention.
As an example, "Horde" would be defined as a unit comprising an untrained rabble with assorted close combat weapons. "Blades" would be troops skilled in close combat with swords or heavier cutting weapons. HOTT has a rather restrictive number of unit types, which I expanded by importing more historical troop types from the related historical rules sets, and adding a few of my own creation. There are now 36 unit types, which may be a little excessive but also gives great variety.
Each unit type has two definitions that accompany it. A unit must be foot, mounted, aerial or water-born, depending on it's primary method of movement. A unit also must be a troop unit, a character or a lore unit. A troop unit represents a body of fighting men, a character represents one heroic individual (probably with a small entourage), a lore unit represents those fantasy units that don't fall into the other categories - Deity, Dragon, Airship and Monster as it currently stands.
A unit must also be defined as either superior, ordinary or inferior, and can be assumed to be ordinary unless otherwise stated.
There also a number of special rules that may apply to a unit. I have dubbed these attributes. Some of these are automatically applied to a unit type, e.g. A unit of Skirmishers always has the Evade attribute. Any attributes may be applied to a unit type - these will be defined in the army lists for each army, giving more variety to the armies.
One of the few things carried over from Battlelore is the damage to the unit, although instead of removing figures as hits are inflicted on the unit, damage markers are placed by the unit. If a troop or lore unit takes 4 hits, it is destroyed. A character can take only a single hit before being destroyed. However, a character can also be used to lead a troop unit, which improves the troop unit's performance in combat and means that the character will not take any damage until the unit (s)he is leading is destroyed. This makes characters powerful but brittle when used on their own - it's a high risk tactic.
Each unit has a combat factor which ranges from 1 to 5. For example. a Blades unit has a combat factor of 3 against foot troops and 2 against mounted troops. A Hordes unit has a combat factor of 1.
There are also a number of tactical factors. For example, attacking the flank or rear of an enemy unit has a tactical factor of 1. Attacking a unit that has 2 or more damage markers also has a tactical factor of 1.
To resolve combat:
1) Add together the combat factor and tactical factors for each side. Subtract the enemy unit's combat factor from your unit's combat factor to give the total factor.
2) Roll an 8 sided die and add the total factor. Look up the result on the table below.
3) Total Result
-1 or less Your unit is destroyed.
0 or 1 Your unit is heavily damaged.
2 to 4 Your unit is damaged.
5 to 7 Enemy unit is damaged.
8 or 9 Enemy unit is heavily damaged.
10 or more Enemy unit is destroyed.
4) If your unit is of superior quality, the enemy's is not and the score is 4 or less, add 1 to the result.
If your unit is of inferior quality, the enemy's is not and the score is 4 or less, subtract 1 from the result.
If the enemy unit is of superior quality, yours is not and the score is 5 or more, subtract 1 from the result.
If the enemy unit is of inferior quality, yours is not and the score is 5 or more, add 1 to the result.
5) A damaged unit receives one point of damage and is pushed back 1 hex.
If the unit has the Evade attribute, it does not take damage but instead makes an evade move.
A heavily damaged unit has the same outcome as a damaged unit but takes an extra point of damage.
A destroyed unit routs and takes a point of damage if it has the Evade attribute.
If it does not have the Evade attribute, the unit is removed from the board.
I have left a few things out to simplify this post, but there you have it - the bare bones of the combat system.