Will there be a significant probability of an option to Defect appearing If we play our cards right?
Possibly, though you would lose everything if you did so. Remember, treason in the Warring States Period was rewarded with the death of your family, even your extended family up to 7 relations away from you.
So would good plans during future wars where we are the commander/general add modifiers to our rolls?
Yes, if they happen to be particularly good or insightful though.
To me it felt more like a Zulu Bull-Horns?
Nope, those are both more or less right. This was more a double envelopment in the style of Cannae than the Zulu Bull-Horns.
Both Duke Ten and General Raizen knew the disposition of the other's army. Duke Ten knew that he was outnumbered by the Chu Army, and that in order to prevent his own army from being enveloped he would need to thin his center while trusting his flanks to be kept secure by his advantage in cavalry. General Raizen on the other hand, reasoned that he needed his flanks to be bolstered by his militia troops in order to prevent his regulars from being run over roughshod by the Qin cavalry. General Raizen believed that his stronger force in the center bolstered by his own presence would be able to securely break through the Qin lines, which it nearly did, while Duke Ten believed that the only way to win this battle would be to crush the Chu flanks and their cavalry support in order to trap the Chu in the center. While both strategies had merit, the dice rolls, and the ensuing battle showed that Duke Ten had outplayed General Raizen at least when it came to maneuver and timing. Had Duke Ten been a touch too late, read bad roll, then the Qin center would have broken and there would have been nothing he could do about it besides trying to order a quick retreat.
By the way
THIS is the guy I'd like us to be more like. Not as much of a..meanie but definitely as armored and mounted. I present the Gyoku Hou Unit!
I will tell you that something like that is a possibility for when you try to start your own unit. I plan on giving you a lot of leeway there since you do have the status to be able to afford, equip, and lead a unit of nobles such as that. At the same time though, you could do almost anything with the make-up of your unit, whether it be adding a buttload of archers or even chariots. Of course, for those who want to try to rough it, you could always try to work your way up from the bottom and ingratiate yourselves with the peasant militia troops, though there are obviously advantages and disadvantages for that option.
Also i'd like to suggest our real unit name to be the Dragon Riders or the Lóng qíshì unit. In time, we will be known as the Qin's Dragon General. The mightiest beast that Qin has to offer.
Naming will eventually come later, after you have made a name for yourself.