Concerning cavalry; I would like to point out that stopping them is not the hardest thing to do with a spear. However, what I find is OP is the tankiness of horses, regardless of their faction, and if they have armor or not.
I often play with the TZ0 clan, which is composed of a lot of warband & NW veterans. On multiple occasions a heavy cav is stunned by a spear, and surrounded by speared infantry, shot with arrows and poked with more spears: the cav easily makes a swift exit after being stunned and the horse is still mid-to-high health.
There are many strategies to counter cav spam and whatnot, I'm not complaining about that. The gold-price of playing heavy cav is also an entirely different subject which should also be adressed. But right now, if we could at least either nerf the horse's hp, or buffer the spears and reduce pokes from a spear off a stunned horse, that would be grand