6 - 1 - 4 - 5 not familiar with 2 and 3.
Keep the preamp/amp for now.
Definitely get decent speaker cables: Transparent, Purist, Synergistic, Audience Au24, Siltech, Acoustic Zen, Kubala-Sosna (Audioquest, Cardas, MIT, Blue Jeans, Signalcable, Monster, NOT!)
Use XLR (balanced) interconnects between your preamp and amp, if you aren't at present.
.
Keep the preamp/amp for now.
Definitely get decent speaker cables: Transparent, Purist, Synergistic, Audience Au24, Siltech, Acoustic Zen, Kubala-Sosna (Audioquest, Cardas, MIT, Blue Jeans, Signalcable, Monster, NOT!)
Use XLR (balanced) interconnects between your preamp and amp, if you aren't at present.
.