Hey Gestalt,
I use a 8.5 on my Falcon 111 and its sweet. Im 92 kgs.I use a 44cm Curtis CR10. Its got a failry wide tip which is good for getting going in lighter winds but not particularly fast. But hey thats the point for light winds.
I would love a 46 cm Goldwing.
They were for sale on Maui for $185 US.

Definitely the Tectonics, they are unreal fins.
The 111 is 69 wide and only 2 ltrs in difference from your board so you should be fine