From what I've heard, I think a lot of people will want Carthage to be more powerful, both to increase the challenge of playing as the Romans (Scipii in particular) and to increase the fun of playing as the Carthaginians.

It seems to me that at very least, Carthage should be very rich and should benefit from a steady stream of available mercenaries. (For all I know, this may already be the case, since I don't have the game.) That way, even if Carthage's own units are not improved, it will at least be able to depend on mercenary armies to help when necessary. The weakness, of course, would be that Carthage would be in big trouble if it suffered some major defeats that led to the loss of revenue. It would not be able to afford having trade routes cut, ports blockaded, or wealthy territories lost.