So I have to ask Don, are the rubber tits on the back side of the rubber cushion intact? They hold the cushion drive in the hub. Quite often they shear off and the cushion rubber is found floating in the hub between the hub and the drive flange. Lots of examples have shown up on FleeBay for sale with missing tits.
If it is floating, then the cushion rubber is probably interfering with those casting flash overs on the drive plate. Most of the skiving appear to be on the blocks of the cushion rubber which are under load when driving and I would imagine that they squeeze sideways and the casting flashovers chew the rubber when they can. I would consider removing the flashovers to minimize any further wear. All things considered, the cushion rubber looks to be in good state.