... a couple of things I found, if using camera on the kite:
I found set the camera for 960 rather than 1080. When in 960 it comes out 'taller' so to speak and you can capture more usefull stuff rather than just the wing tips of your kite when set up as wide 1080. It gives you more chances to catch stuff in the back ground that would other wise be missed. I found you can then post edit the footage and 'cut' off either the top or bottom or even stretch the footage wider and make it 'look' like wide screen, more pleasing to the eye.
If you can, get a big memory card and set camera for the highest frame rate, you can always slow it down when post editing. This way you'll have more 'frames' or more footage to play with so if you want to slow mo, it ends up smoother. Mind you not sure but it might chew the battery a bit more, not sure why, probably working the electronis harder. Oh and really important but make sure the card is Class 10 too, HD footage is fast and memory hungry and class 6 and below just isn't good enough!
Do a test flight. You don't wanna have the big day come and find out the angle or position is wrong! Experiment with mounts and angles.
Make the mounts as steady as possible so camera is not wobbling, even though gopro is amazing at evening it out, less wobble is better.
Try not to get water on lens, nothing worse than a drop sitting on the front taking up most of the screen.
Chuck a good tether/safety line so if mount breaks the camera doesn't go flying on its own!
Have fun,
Robbie