I read more of this thread than I care to admit, looks like a soft modern playfield and some shotty QC.
I question everyone from the top down that's involved in the manufacturing process at JJP! I don't think any idiot would install a post that's effectively a knife-edge onto their playfield. If all of these posts were like that it should have been rejected by management if it was only a few then the assembly folks should have been tossing them into the trash. I just played a WW SE this weekend and still want one, but the soft playfield was apparent on it after only two weeks on the floor (in a busy arcade) it had dimpling the same as reported on newer Stern games (mine included).
I just very carefully inspected my IM as the top posts on the slingshots are a thin one like this one and I don't see any wrinkling or chipping anywhere. So I think Mirco is partly to blame.
Pirates is still only a wish for me so I won't comment on what a fair solution is, but I certainly feel for you all as I know I'd be upset to find that post digging into a playfield of mine. Hopefully, some of the mitigation ideas will end up working out and that you can continue to enjoy what otherwise appears to be a standout game!