As far as I've been able to find (someone employed by EVGA feel free to correct me if I'm wrong), there is NO platinum version of the G3 much less a titanium version at this time.
The P2/T2 still seem to be available, but might be in short supply - all PC part suppliers got hit HARD this Christmas shopping season, especially on higher-end parts.
I'd also personally avoid the G3 anyway, as it uses one of those "fancy name" sleeve bearing fans that don't LAST in high-load usage - the G2/P2/T2 use a good ball bearing fan that keeps going and going and going.....
Unless you are pushing TDP above stock, you shouldn't need a 1600 on that build - a 1300 should be plenty.
Cables might be an issue on a 1300 though, as the Kingpin is a dual 8-pin power card and the 1300 only has 6x8-pin connections on the stock cables (and 2 dual cables IIRC adding 2x6-pin connections).
The 1600 WOULD give you plenty of headroom for overclocking stuff though.
CPU and VGA ports are SEPARATE and NOT THE SAME on the EVGA G2/G3/etc series power supplies - in theory you could dig up a custom cable to use a CPU port to feed VGA card(s) from but it's not standard.
Not a factor anyway since your motherboard uses 2 x CPU connectors you'll need BOTH of them to power the MB.
What is the "11'th" power connector you're talking about, I only come up with 10 - 2 CPU for the MB and 8 total for the video cards if you go with the 4 card option.