What is it about the speakers that you don't like that you are trying to improve?
If you intend to open up the crossovers to rewire them, you will get FAR MORE "difference" by changing the value an internal resistor or capacitor by even just a small amount while you are in there.
Remember that "factory-built" speakers are auditioned in an entirely different setting than your room, and a bit of crossover tweaking may pay off in spades..., if you know what you are doing.