Don't get used to good campaign balance just yet, dvk. The next changes to unit stats might already change that. I think it's too early too make the small factions even smaller. As far as my experience goes, the punic war is still very violent, but rather short. Hannibal just can't find new troops in Italy, and the same goes for the romans in Spain. Maybe Genoa and Emporion should have a higher population and better barracks?
I'd also wait with closing the pass over the Alps. Right now, Rome went there because they saw no other choice. If we remove the free barbs and the boii from northern Italy, Rome will have the option to go east. I think the very best thing would be to somehow copy the situation in RS1,5. Rome always went after the Gauls, but only after defeating endless stacks of barbarians in the Po valley. Shouldn't there be a way to do that in RS2 as well? After all, how are the Cimbrii supposed to invade Italy, if there is no mountain pass? (Oh well, the Bear Warriors just will have to make one

)
And I agree with the removal of Hibernia, the Baleares and Sicilia Medius. We'll probably need some more regions wherever our new faction will be located.
As for Numidia, I don't really know. For one, once Carthage looses in Italy, it concentrates on taking the african settlements, and once that is done, it passes over the landbridge and floods Iberia with troops. In the long run, more regions in Africa will only make the carthaginian onslaught worse for the gallaeci and the arverni. Does anyone know if it would make sense to remove that landbridge, errect a landblock in the East and force Carthage to go naval? Or will they just wander around in Terra Incognita, looking for a settlement that's not there?
EDIT: So I wrote all that for nothing :-P