Here are my thoughts on period specific rules for using Black Powder for the SYW.
Since everyone I play with is familiar with Warfare in the Age of Reason, and our armies are built for that set of rules, I'll use that as a common touchstone.
Standard Infantry: 12 figures. Small is 6, Tiny is 3 and Large is 18.
Standard Cavalry: 6-8 figures. Small is 4, large is 9-12.
Since cavalry 'standard units' represent squadrons, one can opt to mass 'units' from the same regiment into larger 'units' (think the Bayreuth Dragoons at Hohenfriedberg). This can be done during the game but the units must be within 6" of another and it costs a move to organize the squadrons into a mass.
Use of Mixed Formation and Attack Columns are not allowed. Squares are allowed but no one gets the 'form square' rule for charge reactions.
Cuirassiers HTH 9 Morale 3+ Stamina 3 Special:heavy cavalry D3
Guard Cuirassier HTH 10 Morale 3+ Stamina 3 Special: heavy cav D3, Reliable
Heavy Cavalry HTH 9 Morale 4+ Stamina 3 Special: Heavy cav D3
Dragoons HTH 8 Morale 4+ Stamina 3 Special: Heavy Cavalry +1
2nd rate cavalry drop HTH by 1, no heavy cavalry bonus for melee resolution and add 'unreliable'. Freikorps dragoons or hussars add 'marauder' too.
Hussars HTH 7 Morale 4+ Stamina 3 special: skirmish, marauder
Elite Hussars HTH 8 Morale 3+ Stamina 3 Special: skirmish, marauder, reliable,
Freikorps hussars HTH 6 Morale 4+ Stamina 3 Special: skirmish, marauder, unreliable
Guard Infantry HTH 7 Shoot 4 Morale 3+ Stamina 4 Special: Reliable, Elite 4+, First Fire
Veteran Infantry/Grenadiers HTH 7 Shoot 3 Morale 4+ Stamina 4 Special: Reliable, Elite 4+, First Fire
Line Infantry HTH 6 Shoot 3 Morale 4+ Stamina 3 Special: First Fire
Garrison/Militia Infantry HTH 5 Shoot 3 Morale 5+ Stamina 3 Special: Unreliable,
Freikorps Infantry HTH 5 Shoot 3 Morale 4+ Stamina 2 Special: Unreliable, Marauder, skirmish
Jaegers HTH 5 Shoot 3 Morale 4+ Stamina 3 Special: sharpshooter, skirmish, marauder
Pandours HTH 6 Shoot 3 Morale 4+ Stamina 3 Special: skirmish, marauder
This is the tough part. Prussian drill was quite good and allowed them to keep up platoon vollies in a fire fight longer than their opponents. Some have argued to give Prussian musketeers a Shooting factor of 4 instead of First Fire. Perhaps just the older musketeer regiments? For the 1st Silesian War/ first phase of the War of Austrian Succession the Prussian cavalry should be pretty bad, perhaps 2nd rate but good by the SYW.
Austria, France and Britain all pretty bog standard.
Russians give their infantry the 'steady' rule and stamina 2 for their artillery.
Reichsarmee would be all 2nd rate infantry and cavalry. Grenadiers equivalent to everyone else's line.
Prussia; Frederick 10, Ziethen 9, everyone else 8.
Austria; Browne, Nadasty, Hadik, Loudon 8, most 7, Daun and Archduke Charles 6.
England and France; mostly 7s. Marshall de Saxe could be an 8 or 9 but was he around in the SYW? I can't think of any real superior generals for either army.
Reichsarmee; given the tangled staff and organizational problems they'd be 6s.
Russia; a few 7s but mostly 6.