Since the properties of P-Type and N-Type semiconductor are so different, it is impossible to make geniune totally matching complimentary pairs.
So when you see a complimentary pair, they are usually two completely different transistor designs chosen so that they have a similar voltage capability, current rating, current gain, collector to base capacitance and package type. Usually this means the PNP transistor has to be larger then the NPN for the same current capability. Here are some typical chip layouts:
The layouts are different, but they are at least in the same type of layout. A small signal low-noise transistor, a RF transistor, a high voltage transistor or a switching transistor all have noticeably different styles of layouts.
In many ways, the maximum current rating is not that important as the transistor is performing pretty poorly at that point. The 2N2222A and the 2N2907A would be usually used at 300mA or less and a working voltage of less then 50V, and they are great general purpose transistors in this range.
Richard