I actually disagree that #3 is needed if #1 and #2 are properly executed.
Plug-and-play is still an issue for the reasons you mentioned but I’d imagine as newer phones ship with newer OS, that fewer and fewer won’t recognize a GearVR plugged into it.
A 24/7 chat dedicated to GearVR-related issues should be able to handle all other issues. It should be dead simple to actually find this dedicated chat queue (perhaps an insert in the GearVR box to start). Engineers should be well-versed in the classes of hardware, software, and Store problems owners may face, knowledgeable in workarounds, able to handle RMAs, and perhaps offer Store refunds.
Besides a brief mention in the GearVR manual that says “If you’re having problems with your GearVR, please try rebooting your phone and making sure the phone makes a solid connection to the headset”, if you have to include a troubleshooting guide then you have more refining to do.
ps. Andrew and Nick at Samsung have been tremendously helpful on Twitter with troubleshooting, but this is perhaps not the best use of their time. :)