I understand what you mean, shangai brave, but you are wrong, for at least two reasons.
First, most maps do not fit a charging group of cav. We get 2 or 3 open plains out of the 50 villages and cities and then those "open plains" are actually mountains.
Second, Warband is mostly a skirmish game in which everyone is independent and tries to survive independently. We don't have enough players to simulate charges like in a Total War game for example.
For a cavalry charge to be effective you need to be able to hit your target. Horses in this game already lack maneuver which forces them to backstab unaware enemies, because unaware enemies don't dodge. Decreasing maneuver further will mean even more backstabbing and even less charging.
