So we've raised two issues: (a) the late Renaissance-early Industrial siege homgenization; and (b) the "musket gap." I cannot help but wonder if the easiest way to address both would be to simply change what promotions what units could gain based on what Techs were known?
Some tentative ideas:
Catapults, Str 5 Mv 1 cost 100 requires Math & Masonry Techs (inherent special abilities same as in current HiTM). Initially eligible for Combat I, Drill I, City Raider I, Free Upgrade. Upgrades to Cannon with Military Science.
Made eligible for Combat II, & III by Guilds Tech (better training and command & control)
Made eligible for Shock I-III and Cover I-III by Firearms Tech. (use of early Arquebusier support)
Made eligible for City Raider II, and Combat IV by Engineering Tech. (better siege engineering)
Never eligible for City Raider III or IV, Medic or March promotions, Barrage I-III, Accuracy I & II, nor Arctic or Desert, Garrison, Geurilla, Commando, Fieldsman, nor Defence Promotions.
Trebuchets, Str 4 Mv 1 cost 160 (inherent special abilities same as in current HiTM) requires Machinery Tech. Initially eligible for Combat I, City Raider I, Barrage I, Free Upgrade. Upgrades to atillery with Artillery Tech.
Made eligible for Combat II, & III, Barrage I & II by Engineering Tech. (better siege engineering)
Made eligible for Accuracy I, & II by Optics Tech. (better surveying, trigonometry, etc.)
Made eligible for Combat IV, and City Raider I-IV by Military Tradition Tech. (better officer corps, training, and combined arms tactical coordination)
Never eligible for any of the Medic or March promotions, nor Ambush promotions, nor Arctic or Desert, Garrison, Geurilla, Commando, Fieldsman, nor Defence Promotions.
Siege Towers, Str 5 Mv 1 cost 130 requires Construction Tech (inherent special abilities same as in current HiTM). Upgrades to Cannon with Gunpowder Tech. Inititally eligible for Combat I & II and City Raider I-II, & Free Upgrade.
Made eligible for combat III by Gunpowder Tech. (use of explosives and semi-hand-held muzzle-loaders)
Made eligible for Shock and Cover, & Drill I & II by Military Tradition Tech. (better officer corps, training, and combined arms tactical coordination)
Made eligible for City Raider III and IV by Chemistry Tech. (better powder, better supply storage and distribution, better ammo)
Never eligible for Combat IV, nor for Drill III or IV, nor for any of the Pinch, Formation, Commando, Geurilla, Fieldsman, Garrison, Defence, Desert, Arctic, Amphibious, or Ambush promotions
Cannon Str 12, Mv 1, cost 200, requires Gunpowder Tech (inherent special abilities same). Upgrades to Artillery with Artillery Tech. Initially eligible for Combat I, II, & III< and City Raider I, and II, and Free Upgrade.
Made eligible for Shock and Cover, & Drill I & II by Military Tradition Tech. (organizational innovations in training, strategy and tactics that increase field anti-personnel effectiveness)
Made eligibile for Combat IV, Pinch and Formation by Military Science Tech. (improved tactics against muskets and mounted)
Made eligible for City Raider III and IV by Chemistry Tech. (better powder, better supply storage and distribution, better ammo)
Made eligible for Defence I through IV by Replaceable Parts. (use of cannons in combination with earthworks, interlocking fields of fire, quick entrenchement, and field formations)
Made eligible for March and Drill IV by Railroads (better logistics = quicker replenishment of effectives where they are needed, faster transport capacities promoted [through necessity and opportunity] theatre and operational level organization)
Made eligible for Accuracy I & II and Barrage I thru III by Steel Tech (better rifling, better mechanisms).
Never eligible for Desert, Arctic, Amphibious or Ambush.
Artillery identical to the current settings.
Musketman, Str 9, Mv 1 cost 160 requires Firearms Tech. Initially eligible for Combat I, Formation I, Fieldsman I, Garrison I-IV, Drill I & II, and Defence I & II. Upgrades to Infantry with Assembly Line and Rifling.
Made eligible for Combat II & III, Shock I-III and Cover I-III and Formation II & III, and City Raider I & II by Military Tradition Tech. (early mistakes in gun design, and tactical deployment improving, potential effectivenss of massed gun formations against the push of pikes coming to fruition)
Made eligible for Combat IV, Pinch, Fieldsman II,and City Raider III by Military Science Tech (Flint locks with bayonets combined with better training and tactics)
Made eligible for Drill III & IV and City Raider IV by Chemistry Tech. (smokeless powder, lighter stocks minie ball compound bullet types of developments)
Made eligible for Defence III and IV by Replaceable Parts (better equipment repair and maintenance)
Made eligible for March and Medic I & II by Railroads (better logistics = quicker replenishment of effectives where they are needed)
Never eligible for Desert, Arctic, or Amphibious or Ambush.
Grenadier, Str 12, Mv 1, cost 200, +50% attack vs. Rifleman. Requires Military Science Tech. Initially eligible for Combat I & II, Shock I-III and Cover I-III, Formation I & II, Drill I & II, Fieldsman I & II & Defence I & II.
Made eligible for Drill III and City Raider I by Replaceable Parts (improved coordination of combined arms [grenades, breech-loaders with bayonets, various battalion integrated artillery such as small cannon using grapes shot], as well as better ammo, better powder, etc.)
Made eligible for Pinch I and II, Fieldsman II, City Raider II and III and Formation III & IV by Chemistry (improved coordination of combined arms and improved realization of tactical use of combined arms against varoius types of opposing formations/units, particularly older "musket" units)
Made eligible for Defence III and IV by Biology (kind of a filler . . . better food and medical care for the troops!?)
Made eligible for Combat III, March, Pinch III and City Raider IV by Railroads (better logistics, and better ability to create optimum concentrations of combined arms)
Made eligible for Garrison I & II, Geurilla I-II, and Drill III by Nationalism (ideological shifts facilitating different recruitment and training regimens, and totally novel forms of deployment)
Made eligible for Desert Combat I-II, Arctic Combat I-II, Woodsman I-III by Medicine (better food, better logistics and supply distribution, better medical care)
Made eligible for Garrison III, & IV, Geurilla III, and Drill IV and Commando by Fascism (similar to Nationalism, ideological shifts creating new ideas about how a military can and should operate).
Never eligible for ambush or amphibious.
Rifleman Str 14, Mv 1 cost 20 +25% vs mounted. Requires rifling. Initially eligible for Combat I & II, City Raider I, Shock I-III, Cover I-III, Formation I, Drill I, Fieldsman I, and Defence I.
Made eligible for Pinch I, City Raider II, Fieldsman II, and Formation II by Chemistry (better rifling and breech-loading mechanisms)
Made eligible for Defence II, Drill II, and Fieldsman II by Biology. (better food and medical care)
Made eligible for Combat III, City Raider II, March, Pinch II by Railroads. (bolt action and better repeating rifles)
Made eligible for Garrison I-II, Geurilla I-II, and Drill III by Nationalism. (compound bullets, as well as the above noted ideological factors)
Made eligible for Desert Combat I-II, Arctic Combat I-II, Woodsman I-III by Medicine. (better food, better logistics and supply distribution, better medical care)
Made eligible for Garrison IV, Geurilla III, Drill IV by Artillery.
Made eligible for Garrison III, and Commando by Fascism. (similar to Nationalism, ideological shifts creating new ideas about how a military can and should operate).
Made eligible for amphibious by Refining. (carbines and water-resistant cartridges and mechanisms, as well as better landing craft?)
Never eligible for ambush. Only "infantry" should be able to incorporate anti-tank.