How does using broader terms, while keeping options open to players, constitute a board-game NES? Were Fulton's epic NESes, which used such terms board-game NESes, what about Immac's NES, which is even more prescriptive in the units players can use? As for the need for separating two distinct classes of unit, well why separate units at all? After all players will only be playing at the grand strategy or operational strategy level? Because, even if players do not micromanage battles, types of forces make a difference. Siege engines, which are ranged, archers, which are ranged, and skirmishers, which are ranged/light infantry, are all vastly different units.
This was my feeling while writing the rules, and I think this is a good explanation.
I had in mind that, even though players aren't using Archers on a tactical level, that applying some sort of significance to them in a
fantasy setting is important. Elves have better archers. I am being as cliche as possible, and I am loving it.
But all that aside, I felt that archers even outside of a tactical level, can be included in a general "army". If I am modding a battle between two armies, and one of the armies has archers and the other doesn't (and otherwise they are of equal strength), and they fight at the edge of a group of hills - I would say the army with archers would have a real advantage (especially if the player indicated in their orders that if a battle is to occur, archers should take high ground or something).
Even if we throw practicality away, archers are just
cool. It is fantasy! We are talking about leaving terms vague. Like, for example, change Swordsmen to Shock Troops. But I feel in the medieval times, shock troops will pretty much have swords... right?
And as for Spearmen. I always think medieval towns have a bunch of spears lying around. Farmers with pitchforks, altering those tools to become weapons, and so on. So while it is a specific term, that they are equipped with spears, I think it makes sense. Can't imagine it being anything else. Spearmen are town-only units. They are weaklings compared to Pikemen. And when I think of medieval defenders, I think of pikemen.
These were my thoughts when coming up with those rules. I could always make it vague and say, "Attack unit" "Defense unit"... but if a player really wants to be creative, he/she can just say that their army's Pikemen are really guys with massive swords, but they serve as part of that same Defense Specialty, and have the same effect as pikemen.
The best point I've seen here is perhaps compounding the Town-Level units into a single unit called Militia.