No, because as I said, then there would be little that can stop cav rapetrains.
IMO cav "rapetrains" shouldn't be easy to stop. Just like a group of archers camping together and watching each other's ass is hard to attack. Besides, they are called "charges" and not "rapetrains".
Currently, all the horses, from light to heavy, are sort of the same. Everything is about catching people unaware, even with a tank horse. I'd like to keep it that way with light horses, but change the role of heavy horses.
Heavy horses should be made for charges. But because in the game we deal with extremely small scale skirmishes, there is little point in charging the back or flanks of a "formation" because there usually are no formations. So every charge translates into a front charge, with the enemy aware and probably ready. Here's where the horse rearing destroys the gameplay. A charge should mean chaos in the enemy blob. But if the horses make a dead stop in front of it, no chaos is going to happen.
So I'd like horses not to stop, even if they are catched by a pike. If we could mod it, the best would be making the rider drop from the horse because of the inertia, suffering heavy damage and let the horse continue without rider at a slower pace, through the enemy group.
Of course, most light horses should die instantly when crashing into a pike. To balance it out, their maneuver (and maybe speed) should be upped. Buffing light horses maneuver will also help increasing their anti-cav strengths and make up for the general lack of any inertia or realistic "maneuver" applied to humans, especially with the current agi trend. Heavy horses, on the other hand, shouldn't die to a single pike hit. However, they are not made for killing the unaware or the lonely pixie, so their maneuver should be lower than now.
So basically, increase the differences between horses.