I find it easier to keep track with photographs rather than lists, so I made these "muster parade" photos of the forces I have for the coming Macedonian Wars campaign. These were done using Skitch, which is easy enough to use, and has both a desktop and iOS version.
First, the Polybian Romans. The bulk of this force is the infantry, here arrayed in the quincunx (chequerboard) formation used by the Romans in this era. I painted the hastati and principes in two different colour schemes (white and red) to distinguish them visually, but in most rules there is no difference between them. The trairii can be easily distinguished by the spears. The cavalry I've grouped into two - the more "Roman" looking ones, and the "bunny-eared" ones which look like Italian allied cavalry. Again, there is usually no difference in how they play in most rules. The single based mounted commanders were for Warmaster Ancients, but each is one-third of standard DBx frontage, and standard depth, so they cold be fitted onto a 40x30mm cavalry base if need be at a later stage. This army is mostly complete, with some command bases spare to be painted: I might base some of them in small dioramas, for visual effect. Not pictured is a Praetorium tent from Baueda, which can be used as the baggage element.
Next is the Carthaginian Army. I started painting this with the aim of making a small (12 bases) army, so I would have a matched opponent for the Polybian Romans. This army is much smaller than the Roman one, but for the coming campaign, it will be joined by allied forces from the other players (and the Spanish army, below). In the wings waiting to be painted are a few more bases of foot (2 bases of African troops in captured Roman armor, 4 more bases of Poeni infantry), 4 more elephants (because everyone who paints a Carthaginian army overdoses on elephants ...), 2 more Numidian bases, and a separate Gallic army (12-14 bases) I'm painting, so eventually I will have a Carthaginian allied army of reasonable size.
Finally, the Spanish, most recently painted. I've grouped the Balearic slingers with them, but the Balearics functioned as mercenaries for so many armies in this era that they could be used in almost all of them.