Your equipment is decent, though I agree with UE's suggestion.
Anyways, I still think you can extract some benefit from an aftermarket cable.
If you want the sound to be smoother and warmer (but a bit slower and less transparent/revealing), then go for any good quality copper cable. There are many makers to choose from. Cardas, Double Helix Cables, ALO, Jena, Moon Audio, just to name a few. This is the cheapest option.
If you want to retain the same general sound signature of the stock cable but enhance resolution and speed, get the APuresound V3 (Silver-plated copper). This is the second cheapest option.
If you want the most transparent/revealing and fastest cable, get good quality silver. Moon Audio uses 6N purity silver for their Silver Dragon Version 3 (not version 2). Double Helix Cables uses 7N (higher) purity silver for their own silver cable, though it's more expensive. IME, the sound of silver will be more dependent on your system than other cable materials, but will also yield the greatest improvements if the ancillaries are of high-quality. Silver is also the most expensive option.