The biggest hurdle to researching anything about Carthage is that the bulk of surviving written history was written by Romans. This is like being in the year 4170 and trying to research the Soviet Union with only old copies of The New American as research material, or researching the Bush administration using nothing but the HuffPo archives to draw on.
The Roman republic practically invented the concept of "just war", bellum iustum, and were very conscious of the need to make sure that the bad guys were understood to be bad guys. Also, at the time of the Punic Wars, Rome was still very much in love with its self-image as a republic of yeoman farmers, although there was hardly any farm dirt left on its citified hobnailed sandals by then. The mercantile empire of the Carthaginians, based on buying stuff one place and moving it someplace else to sell, looked effete and decadent to their eyes. If you want to know that the Romans thought of the Carthaginians, all you have to do is look at the Ferengi characters on Star Trek.