Hey mate
I go to Fraser every year at this time, I'm also heading up on Sat 21st for a week and yes I'll be taking a kite and board. The thing with the eastern beaches is there are a lot of sharks, particularly while the tailor are running.
I've had a session or 2 around the Cathedrals but only at low tide sticking to the shallows, there is no way I personally would be heading out back of the breakers, but that's just me.
Last year I had a great session up at sandy cape near the lighthouse, tide was perfect and there is a nice little bay that formed a shallow lagoon. Also, on the western side there are options depending on wind direction.
I'll be taking a 2013 Zephyr just in case the opportunity arises, so of you see me out come say g'day