Reading all the above (phew) I get the impression that for the average (not super-expert) Hackie builder, the thing to do is wait
I have already managed to max out my GTX970 and am salivating over the prospect of a 1080 "someday" -- but it looks like "someday" will be at least 6 months from now, when Sierra is stable (and braver souls than I have figured out the implications for Hackintosh-land) and NVIDIA has released web-drivers for the 10xx cards. At least that's my "executive summary" of this fascinating but discouraging thread. Am I getting the message?