Crion - I can identify with all of that, having been a Russ Andrews Super Purifier Block user for years. It has a dedicated earthing terminal which I run to star earthing rods in the back garden with very low impedance cable (in addition to the standard mains earthing of course). The difference when the dedicated earth is unplugged is noticeable. You can also chassis earth each piece of equipment, as you've suggested, but it depends on the specific piece of gear as to whether this provides benefit or not, very much a suck it and see thing.

HC: 861v4/ID40/LPS, DSP5000, DSP5000VC, DSP3100, SW1600, HD621, Oppo BDP-105, Sony VPL-HW55ES
2-Channel: Oppo BDP-105, TEAC VRDS-7/Trichord Clock 3/PSU, 551, Quad 303, Harbeth Compact 7ES-3, Kimber cables, Russ Andrews mains and supports.
Previous Meridian: 5000C, 5200SL, 7200.2, 6000, 562V.2, 568.2mm, 800v4, 808.2i, 818v2/v3, 861v8, 502