What would an authentic Bosphoran Kingdom army look like?

[Ludens]

I'm guessing from the troops available that it's a mixture of Hellenic and steppe units, though I'm struggling a little to imagine how horse archers would work together with infantry. What would be in a 14-unit stack?

How would you deal with Sauromatae horse archer armies? I've avoided them up to this point, opponents who you can't catch sound like an exercise in frustration. There's some foot archers with even longer range who'd integrate well into a regular army, but would they be the target of every enemy horse archer?

I've been thinking about this for a bit. My impression is that steppe armies relied on harassment rather than direct fire-power. Even in set-piece battles they used a cycle of high-speed attacks and retreat. I doubt that they were able to score many hits (and casualties), but their targets would suffer a continuous barrage of arrows while being unable to strike back. This is terrifying even for experienced warriors, so the end result is that the target is goaded either into attacking or retreating. If the attack is coordinated, the horse archers simply fall back. If the attack is uncoordinated, they surround and cut down any groups that get separated from the main army.

In other words: to fight a steppe army you need to stop thinking in terms of "holding the field". The nomads don't care about the "field": the steppe is huge and they do not rely on agriculture. For a nomad, the most important thing is survival. He is not fighting for land, or glory, but to ensure that he, his family and his tribe make it through the next winter. The harassment tactics are part of that: they rely on persistence rather than damage and minimize exposure to enemy weapons. Countering these by recruiting foot archers or employing horse-archers of your own is quite likely to make steppe armies back down. They are not in it to demonstrate their superiority. Even moderate causalities can severely affect a tribe's ability to protect their land, and survive the winter, so they simply avoid risky targets.

So that explains how horse archers were integrated into settled armies: they were used as a screen to protect the heavy cavalry and (if present) infantry from being constantly harassed by hit-and-run tactics. None of these concepts translate very well to the TW engine though, so attempting to simulate history here will be very difficult.

Another element that cannot be simulated well is logistics. Steppe armies do not use supply lines or bases: their camps and herds travel with the army. (Or should I say that they are the army? Nomad society does not have a distinction between military and civilian.) In this, they can outlast and outmanoeuvre settled armies. However, this bare-bones approach to logistics brings its own problems: if they herds are threatened, the nomads have to back down since their survival depends on it. Also, they derive their superior mobility and endurance from their horses (every steppe warrior worth his salt has several to serve as remounts during battle), but these do require large amounts of grass. The nomads themselves may have very basic needs, but their herds and horses require them to move constantly. Again, this is not something that can be simulated properly in TW.