I guess I would ask what musical attributes are you looking for? How do you feel your system is lacking? Are you looking for cables that provide more power and fullness, or cables with more speed and resolution? Also, do you prefer a more immediate presentation, or a more laid back soundstage? Front row or mid hall?
You cannot have it all, no matter what others may say. It's all a matter of balancing the sound to suit your tastes. Some do it with equipment, some do it with cables.
Before we can give you proper directions, we need to know what direction you wish to head in, east or west.
Cheers,
John