I'd really love this feature, if added (as part of a sword-cav regiment :D), and was thinking of maybe adding another feature to this, to make the charge more 'chargey'.
Maybe, if you press C (or whichever key would be used), you shout, extend your sword/sabre, and give your horse a little speed boost, for as long as you hold your sword down (which would stop after a moment, just like lance couching), which then needs to 'recharge' for some time, like the lance after couching.