One thing I like about Impetus Punic War(s) period is the versatility that can be utilized, not only to build armies of different configurations, but also that minor additions allow one to field armies of different nations. Iberians for example are used by virtually all parties in a form of mercenaries, but very tiny addition (in this case cavalry) allows their own army to be fielded for Basic Impetus. Of course since they do overlap with Carthage, their opponent would be Republican Rome but in any case, it allows more flexibility and freedom to choose from.
BI allows certain armies to be tested without major commitment (I tend to dislike proxies) and once found suitable, they can be expanded for the full game (or multi-basic-impetus) quite easily. If not, then there is always option to hire them as mercenaries for other armies.
Iberian army appears quite strong with virtually every infantry unit being capable to engage in melee, and all of them being armed with javelin. Being FL, they have pretty much the initiative to choose where and when to engage slower, albeit stronger Roman legions. There is also very strong cavalry contingent of two CL and one CM, meaning that Roman cavalry will be hard pressed. Celtiberian contingent will make nice shock surprise once legions have been softened up somewhat… I can imagine that there will be some rather interesting battles lining up.
That said, I am in progress to paint up some French Grenadiers and Voltigeurs on the Napoleonic side of the story and also have gone about half way through the work on my new tabletop arrangement.