I have just started playing the game and am overall very happy with it.
I have noted that the infantry divisions and cavalry regiments have skirmishers and videttes gathered as separate units which can act independently of their parent unit. This is more akin to Napoleonic times when the light companies of the various regiments would be gathered together into a "light battalion". I cannot recall any instances in my reading where skirmishers were sent far afield from their base unit to circle around enemy forces like might have happened with the light battalions of old. It may make for a more interesting game, but to me such actions by skirmishers are not realistic to the Battle of Gettysburg.
In the Civil War generally the skirmishers came from a company or two selected at random which was sent 100 to 300 yards or so in front of the base unit when such a unit was stationary. These were not special companies. Their role was mostly one of harassing the enemy forces. When the enemy forces advanced, they would retreat back to their base unit. When their main unit advanced they would stay put and absorb back into the unit when it reached them and then join the advance.
The companies of skirmishers would spread out in front of the base unit and take pot shots at the opposing troops. Since they were "hiding" in many cases in brush where available they were harder to hit. On the other hand, the damage they inflicted on the opposing forces was also minimal. It was more psychological than anything else. Yes, the skirmishers did inflict casualties, but not in any significant amount. Instead their major impact was to reduce the effectiveness of the fire of the unit which they were firing at. Thus, an infantry brigade or artillery battery under skirmish fire ought to be less effective and inflict less casualties than a unit not under such fire.
Thus, to me it would be more realistic if instead of having separate skirmish units each brigade when stationary would send out a few soldiers (maybe 10%) in front as skirmishers which would act appropriately based on the brigade's actions and the actions of the enemy. However, that would require a major change in the game.
Those are my thoughts at least.
Karle