The army as it sits has 3-Roman Legions (12 stands), 2 Gallic cavalry stands, and 4 Roman cavalry stands. Officers, standards, and musicians are mounted individually. (2 Italian Legions are finished and almost completely mounted, this will allow me to use them as a Consular army (2-Roman, 2-Allied Legions).
The thing I liked about IMPETUS is the ability to fit any number of figures on a base, In my case, 6 Hastisi, 6-Princeps are on two of the bases, 4-velites on another, and finally 6-Triarri on the fourth stand (with some type of officer to balance out the stand.
I think it shows the Roman "checkboard" approach fairly well. I was going to increase the depth of the stands, but wanted to stay "legal" for the game, in case I play at a convention.