New member, so only just seen this.
One aspect of the battle that gets neglected - mainly because you would need to extend the table for several yards to fit it in! - is the diversionary action by Armstrong and the Pennsylvania militia at Van Derrin's Mill, over on the Hessian wing of the Crown positions. If you have the McGuire books, he provides some useful background info on this, which is a fascinating "what if" involving only Hessian and Militia forces.
The Rebels advance from Norriton along the Mahatawny Road beside the Schuykill River, with the idea of threatening the left wing of the Crown forces and stopping Knyphausen from adding his troops to the repulse of Washington's main attack. In real life, they were held by several companies of jaeger (including a mounted company, and a pair of those "wall guns on wheels" that the Perrys do) at a stone bridge over the Wissahocken Creek and a large stone mill.
Rebels - Maj Gen Armstrong, Brig Gen Potter - 1500-2000 men
7 regiments of Pennsylvania Militia, including one armed with rifles (skirmish capability)
1 troop of Phiadelphia Light Horse
4 x 3- or 4-pdr cannon
Hessians - Maj Gen Stirn
Lt Col Wurmb: 4-5 companies of Hesse Cassel and Anspach-Bayreuth jaeger (300)
Reinforcements:
- Grenadier Bn Minnigerode (400), 1.5 miles away
- Brigade Stirn - Du Corps/Erbprinz Regt (500); Donop Regiment (380), 2 miles away
There is a map of the advanced jaeger positions in Ewald's "Diary of the American War" and a more general map of the area around the Creek and bridge in McGuire. My club has gamed this twice, using the British Grenadier rules, on the basis that Armstrong decides to turn the feint (at one point they did actually cannonade the Hessians' main camp) into a more serious attack. The Crown player dices for when his reinforcements arrive (with a "not at all" option); the tough bit for the Rebel player is to get militia to advance in a narrow column over a bridge defended by riflemen. Both games were Hessian wins, but the second could easily have gone the other way (the militia never got across the bridge in the first one).