A nice rules framework. I have the following questions.
What is the "Base Saving Throw" for units? 5+?
Lt Cavalry can move as far in one turn as Heavy artillery can shoot. Since Lt Cavalry appears to assault and absorb damage the same as Heavy Cavalry what is the advantage of the slower moving Heavy Cavalry?
Artillery can't Assault, but can they still fire while being Assaulted?
There wasn't a basic saving throw, it is either formation or opponent dependent.
Artillery ought not be allowed to fire in base to base contact, otherwise they become something of an assault unit.
I hadn't spotted the cavalry quirk - you're right there. I think lights would need penalties in combat vs infantry and vs heavy cavalry to balance them ought.
Most cavalry in 18th century battles would fit under the "heavy" battle cavalry designation.
I'd argue that artillery (as opposed to battalion guns -which supplemented infantry) of the period can and did *take* assaults (ie when emplaced had *another* unit move ie charge into contact/melee/close combat.)
But they ought not be permitted to move into contact.
They don't *make* assaults.
Any artillery caught/contacted on the flanks or otherwise limbered should be considered destroyed.
Emplaced artillery (ie unlimbered in field or unlimbered in field fortifications) should either get a shot at a unit charging it frontally or one of two bonuses in melee depending on how it's emplaced or a penalty to a charge test to reflect the battery standoff fire.
I'll put my thinking cap on as to sub-period differences.. eg Marlburian v WAS/SYW v AWI v FR v Naps.