I do not understand reducing the cav speed even further, heavy cav is slow af as it is, basically you have to take agile/faster horse or nothing if you want to move around, slowing it even further is just not justifiable.
I agree cavs should be reared from running into each other.
Fun fact if you know you're about to get reared up because you're going too fast towards a wall you can deny the rear up by jumping, horse will hit the wall but because of the animation of jumping, you won't get reared lol.