Played this scenario through as Mercenary side, against the AI.
Generally, the AI didn't "do" anything. I think it had trouble getting the mercenaries it hired to Carthago - so it was outnumbered, and stayed in the city. Made for an easy game.
I took Sardinia from the AI. Had to send some of my troops by boat to reinforce the troops there. Then the "Roman blackmail" fired (in which Rome takes the island from Carthago). The island became Roman. Not that much a problem, but my troops and my boats just disappeared. This seems a bit strange: if you play the Carthago side your troops are dumped in Carthago - if playing the mercenary side I would expect the troops to be dumped somewhere in friendly territory, or lacking that, being able to fight the Romans and try to escape.
As the AI didn't do much, I managed to take all towns except Oldia (which was taken by "barbarians") and the inland town (Hecatompylos), which was still in possession af Carthago. A small Carthago army was still around, being chased my my mercenaries. After taking Carthago the enmey morale dropped to 3, mine was 180. A few turns later the game ended. I had 1400 VP, 179 morale. Carthago had 700 VP, 13 morale, and no strategic towns. I had (only) a minor victory..... I don't see how I could be more victorious....