Here are a couple thoughts on Accuracy promotions. First, I think Accuracy promotions should require Siege Warfare tech.
The reason to change this is prior to Siege Warfare and the Catapult, there are two Siege units available: Battering Ram and Ballista. I am responsible for both of these units, and my purpose for them is that they would split the abilities of Siege units. Battering Ram can remove city defenses, while Ballista can deal collateral damage and range strike. Ballista is not supposed to be able to bombard defenses at all. Catapult is the first unit that gets to do everything (city bombard, range strike, and collateral attack).
At the moment, Ballista can bombard if it gets Barrage I and Accuracy I (possible with Archery Range + Mercenaries or Archery Range + other civic + Charismatic trait). This is not what I intended. Restricting Accuracy to Siege Warfare will prevent Accuracy Ballistas unless you save your promotions. At that point, it's easy enough to upgrade Ballistas to Catapults that it doesn't matter.
Second, Ram units cannot get Accuracy promotions. Accuracy requires Barrage I or City Raider I. Rams can't get City Raider because they are defend-only and can't get Barrage because they don't have the collateral damage ability. What if Accuracy required City Raider I or Drill I? It would force you to split your promotions between increased collateral damage and increased city bombardment. Only Siege Ram would really benefit, but I think Siege Ram needs to be able to keep up with Trebuchet in the Medieval Era.
The reason to change this is prior to Siege Warfare and the Catapult, there are two Siege units available: Battering Ram and Ballista. I am responsible for both of these units, and my purpose for them is that they would split the abilities of Siege units. Battering Ram can remove city defenses, while Ballista can deal collateral damage and range strike. Ballista is not supposed to be able to bombard defenses at all. Catapult is the first unit that gets to do everything (city bombard, range strike, and collateral attack).
At the moment, Ballista can bombard if it gets Barrage I and Accuracy I (possible with Archery Range + Mercenaries or Archery Range + other civic + Charismatic trait). This is not what I intended. Restricting Accuracy to Siege Warfare will prevent Accuracy Ballistas unless you save your promotions. At that point, it's easy enough to upgrade Ballistas to Catapults that it doesn't matter.
Second, Ram units cannot get Accuracy promotions. Accuracy requires Barrage I or City Raider I. Rams can't get City Raider because they are defend-only and can't get Barrage because they don't have the collateral damage ability. What if Accuracy required City Raider I or Drill I? It would force you to split your promotions between increased collateral damage and increased city bombardment. Only Siege Ram would really benefit, but I think Siege Ram needs to be able to keep up with Trebuchet in the Medieval Era.