I did like them, but they did make other unit lines a bit pointless. I could agree with either option (adding them or not).
What I liked:
- Dedicated scouting units after the ancient era
- Mobility
- Low cost (if you needed just any unit ASAP, or for map control)
What I disliked:
- Their mobility and sight made horse units less needed
- Too many AI units on higher difficulties
- Spears were VERY situational (just look at the table, anti-mounted is their only role)
Historically, light spearmen were THE most common military unit until late medieval times. Only few cultures had a standing army of heavy infantry like Greece, Rome or partially Carthage (they could have them because some sort of "middle-class" existed in their societies, along with a gold-based economy). Most others had a permanently armed and well-trained nobility, fighting usually from chariots or horses, which was supplemented by recruited townsfolk in times of need (Examples include Egypt, Persia, the Celtic or Germanic tribes and practically all medieval European kingdoms).
Those militiamen where either armed with (low-quality) bows or spear+shield. Other protective gear was rather uncommon.
Notable exceptions include medieval Britain, where commoners were well-trained with the longbow, making light spearmen mostly obsolete. The late-medieval pikemen armies that originated in Switzerland are another, but their creation had a lot to do with the urbanizationa and the reapperance of money-based economy we find in the late medieval era - and gunpowder of course.
The conclusion for our game units are:
- Light spearmen were THE standard cannonfodder unit of ancient/medieval armies
- The anti-mounted role of short, one-handed spears is traditionally exaggerated in civ games
- Greek hoplites have much more in common with Roman legionaries than with other spearmen (and should probably be a variation of the swordmen, not the spearmen).
- Then again, they were one of the few spear-armed units that really had the "density" and formation to be especially good vs. mounted units (If attacked from the front, of course).
SUMMARY: I suggest seing spears as generic light infantry instead of a dedicated counter-unit.
If we look at this table:
The secondary defensive roles could easily be taken by spears, as it was in reality. I guess this wouldn't need much explanation.
The anti-mounted role could be fulfilled with a small (25% max) bonus for spears vs horses and/or additional promotions, IF we need it at all. It's a Civ tradition, but hasn't been as important AFAIK historically. Also haven't see the AI mass-produce horses.
The healing role is fully artificial and gamey, but I guess replacement soldiers for high-class units would come from the militia, so healing on spears might make the most sense.
The scout role is most difficult. Sure, if we see spears as generic light unit, they could have this role, too. But it's not what you'd expect when looking at the unit. Additionally, it might overload the spear units with too many roles. Finally, it might be hard to balance a front-line unit (that needs to survive a few hits) and a scout (that needs to be weak to compensate for the fast movement).
Maybe archers as scouts are a better option? They are pretty weak if they are on open terrain and without support, so I don't think giving them mobility and sight promotions would make them overpowered. Those promotions are of little use when they stand behind spears or iron units in a larger formation anyway IMO. And even less when they garrison a city. They should be unable to ever get the move-after-attack promo, of course.
I really think archers getting the scout role deserves a second thought.
