That's a good question worthy of discussion, David. I think perceived speed is down to a few things, but for me the key is how well the leading edge of transients is resolved. This in turn is down to the design of the power supply. If the amp can respond to instant current demands then it will sound faster and more dynamic.

Thinking about the two ends of the spectrum, Naim amps sound fast because of their tightly regulated power supply, no matter what you think of the rest of the sound; conversely, the Quad 303 sounds 'pipe and slippers' slow and always has done to my ears due to an under-specified power supply with poor current delivery. It is liked exactly because it removes those edges! These are simplistic examples but I'm just trying to show a general trend.

Do you still have the Wilsons? I would imagine they need big, tightly controlled power behind them. Have you considered a Chord power amp, or even a Krell (but not all models)? For preamps, it's a no-brainer for me - the Pass Labs range beat everything I've ever heard, including Chord preamps.  You may even like their power amps (if you can take the heat output).

I Know what you mean by slow audio.
I had a SUPER quick set up about four years ago. It was old Classic John Farlowe Exposure amps which were the II pre amp with the off board PSU weighing in at 30kg and the IV DR power amp. These powered a pair old Classic no crossover Epos ES11 bookshelf speakers. I loved the sound, the amps had the speakers by the balls and the speakers did exactly as they were told. The rhythm and pace was incredible. The music would start and stop with incredible pace.