I use three artillery and maybe two or three howitzers when they become available, around 6 line infantry, usually 4 skirmishers and 4 cavalry. I use only a double line and not a deeper formation. If I have slots left I will usually use more skirmishers.

I put 3 infantry either side of my guns and the longer ranged infantry on each flank. I place the cavalry to the rear of the flankers. They are best for chasing routed units, of course though I may risk an attack on flanking enemy artillery. When you kill their guns they will come to you, rather than sit and be pounded. Then you can watch them get hacked to pieces by your guns and infantry.