Cables will not speed up your system plain and simple.
In terms of a what a good cable will offer - more inner detail, air, extension, tone, and dynamics - NOT transient speed. That said - I’m a big believer in silver cables. I use audiosensibility signature line.
Your digital front end is where you need to focus - the DAC and streamer/transport are absolutely critical for transient fidelity and speed/timing (PRAT). This is where you should be focusing.
The major characteristics of digital as you move up the chain are in regards to timing, and jitter. This means : transients, PRAT, staging, imaging and detail. Simple changes like using the i2s input of a DAC will help in this regard. The power supply to your digital gear is very important as well.
This is how you will be able to optimize around your amp (assuming it can ever be "quick" enough for your needs)