Piggybacked artillery fire is too dangerous. Infantry brigades approaching artillery in the open should be prosecuted severely. In the woods, of course, it should be attenuated. This could work. Charges would still be allowed by non-dispersed infantry that fired during the artillery phase.
Cavalry can retreat all the time automatically.
I posted a suggested for a possible one-hexside facing shift for infantry when approached in the enemy turn. They also seem too random. Again, see the above notes regarding the breakdown of command during this battle. Brigades often fought alone without even divisional command contact. I think this is represented rather well.