Just a followup, but I got my ticket set up through British Airways 800 number. It's pretty much set in stone now (unless I change dates later) but I still need to pay to get it actually ticketed.
Here's what it ended up being. I couldn't go to Queenstown like I wanted because it was an unallowed codeshare, and I changed things around to minimize mileage, actually, because I was trying to maximize vacation time. Ended up being about $7500 for a DONE4 after taxes, a touch over.
ATL-ORD
ORD-LAX-AKL
AKL-CHC
CHC-SYD
SYD-JNB
JNB-CPT
CPT-LHR-ZRH
TXL-LHR-ORD-ATL
I'm not at all maximizing miles or stopovers, and probably should've done something more clever in North America, but that's where it stands. I'm looking forward to the vacation, it's about 6 weeks long.