I get into this a bit in the designer notes, but the rise of cadenced marching is one of those things that really creates the warfare of the SYW. Until I had started to study for the game, I hadn't realized that cadenced marching had effectively been lost in the west since the days of the Roman Empire until the early 18th Century. It doesn't seem like a big thing, but if you're on a simple road march, having everyone "in step" really tends to make the whole move faster (as otherwise, your mob tends to move at the rate of the guy with the slowest amble.) If anything, having a consistent step and rate of step is even more important when it comes to moving as a formation and changing formation.
As with a number of other things in the 18th Century, the return of cadenced marching came from the Prussians, as it was instituted during the days of Frederick's father.
With that simple step (pun intentional), much more elaborate and polished movements because possible on the battlefield. However, at this point in time, what was lacking was flexibility. The movements were efficient, precise, clockwork like, but at the same time, they introduced a very real rigidity. Frederick was always experimenting with new ideas, but even at that, the rigidity never left his army.
That rigidity was reinforced by a real "rigidity of thought" in European leadership at the same time. The whole "science of war" thing. This wasn't new. If you think to Vauban and his very precise rules of how to build a fortress, and how to take a fortress you see that. Everything must be done "just so". That's what set the great leaders of the era of Linear Warfare apart (Frederick, Marlborough, Eugene, Saxe), they were willing to "break the rules" when it came to it.
Yet, even when Frederick broke the rules, he was still bound by the conventions of the day. If you look at Leuthen, while his classic oblique attack was "new", it also worked to the clockwork methods of the day, leaving his army in a conventional formation in the conventional way.
So, armies in that era had a pretty standard battle formation that they would set up in. One good place to see it in game is Gross Jaegersdorf
Attachment:
Marching to doom.jpg
Having the arty out in front is a bit odd, but you can see the traditional formation pretty clearly here. You have a front line of infantry, with a 2nd line 200-300m behind. (At times there will be a 3rd line serving as the reserve. If you notice, at the ends of the two infantry lines, there are infantry units arranged to seal off the ends of the "box". Those would typically be grenadiers, and they were to prevent enemy cav from looping in on the rear of the front line. Then, your own friendly cavalry would be out on the wings.
Even at Leuthen, after his brilliant march to the Austrian flank for the Oblique Assault, you can see that classic formation in large part.
By the time of the French Revolution, armies (especially the French) had managed to figure out some ways to be much more flexible, (though we still have waaaaaaaaay too much freedom as gamers.)
I'll post up some other stuff on other aspects later.