By stands and individual figures. Each stand and some individuals have a combat value, this is the number of dice they roll in combat. Some modifiers will add or take away dice . Other modifiers might add or subtract from the total. And some things may allow re-rolls or drop the highest or lowest dice rolled. (maybe not all of those will be part of the proceedings)
Multiple units can combine their roll if they are all in full contact with the enemy. This way 2 or more weaker units could “gang up” on a single stronger unit. Or several individuals could group together.
In hand-to-hand combat each side rolls the number of dice allotted and then the totals are compared. The loser is removed from play. If there is a tie the combat continues in the combat phase of the next player’s turn. If a “unit” which includes a stand and one or more attached individual figures or multiple individual figures acting together loses the combat roll even odds to see who gets removed from play. For example, if there is a stand with 1 leader figure roll 50/50; if there are 3 figures roll 1-2/3-4/5-6. Alternatively, remove standard-bearers and musicians first, then randomly determine which, officers/leaders/heroes/stands get removed?
A musician or standard-bearer might add 1 dice to the total combat dice (but may not be able to fight on their own?). A unit that is uphill or mounted might add another dice. A leader attached to a unit might allow a re-roll of 1 die (player’s choice, presumably the lowest die).
A stand of goblins might get 2 dice, while a stand of dwarves might get 4 dice. A large beast like a great dragon or dinosaur might get 5 or 6 dice (or more).
Procedures apply to both small arms and artillery, unless noted otherwise.
As with combat each stand and some individual figures have a ranged combat value (maybe different from their hand-to-hand combat value?). And, as with hand-to-hand combat, this is the number of dice they start with. Both the firer and the target roll (do I need a third attribute for a unit's defense/"resistance" versus firepower? hmmm, getting away from simple?), but only the firer can inflict casualties (alternatively, they can return fire if able?). Modifiers would include removing dice and/or adding/subtracting from the total for longer range, target in cover or armored, etc. Multiple units do not combine their rolls; each fires separately. Totals are compared and if the firer’s total is higher the target is removed from play.
Some of my thinking behind this: Again I think the procedures/mechanisms are fairly simple, and basically the same for hand-to-hand combat, small arms fire and artillery fire, so no need to learn different basics for each. (as usual, keeping in mind these are untried half-formed (and half-baked?) thoughts). I also think it would make for quick resolutions and fast games. I don’t think morale rules would be needed, as units and figures would be removed from play and eventually one side or the other (or both?) would either fulfill victory conditions or become unable to through lack of troops. This doesn't mean units are fighting to the death, but just to the point that they are no longer effective.