Great lists and suggestions. Here's a couple more:
tube of triple anitbiotic. Small cuts get infected quickly
Insulated water bottles for all crew for longer ice off boat
Triton or insulated plastic tumblers for drinks on board, again for more effective use of ice (ice is precious)
flushable wipes(clearly not to actually flush, just staying "fresh")
1 sharp knife checked in Polar cooler because sometimes you get lucky but most boats don't have one