But what do you think about my suggestion to add attack bonus against Musketmen too, I think that if it can be faster to act than unit with a rifle (that's the reason of the advantage, though it should because of that reason instead have 2/3 first strikes, but that would Riflemen units w/o counter), it's also faster to act than unit with a musket. Though more modern units than Rifleman are faster to act than Grenadier, older units than Rifleman should be much easier to beat, not just a bit.
Rifleman defending: 12.00 vs. 9.33
Musketman defending: 12.00 vs. 9.00
With my suggestion:
Musketman defending: 12.00 vs. 6.00