"So, how to fix that? My new Pas Labs phono preamp has a capacitance setting, pretty much on the fly. There’s a knob on the front panel. As far as I could see, standard wisdom said that MC cartridges are not much affected by capacitance. Set it to 100 and work with other adjustments. And that’s not at all what I"m finding.
When I raise the capacitance knob to 320, the treble is tamed and the bass seems stronger. That’s not what’s supposed to happen. I am leaving the capacitance set to 320, the cartridge loading to 160, and I’ve raised the rake of the tonearm to enhance the treble just a bit."
Are you sure you’re not confusing capacitance with impedance? Capacitance shouldn’t have any effect on the sound signature of an MC cartridge, though there are some manufacturers that provide settings in the thousands of picofarads to tame the high frequency ringing that MCs produce but the jury is out as to whether that has any audible effect.
Increasing impedance can brighten the treble noticeably when raised to too high a value. The impedance load as a rule should be ten times the value of the cartridge’s internal impedance. The Shyla’s being 12 ohms thus VPI recommends a 100-ohm load.

