Paddle mount is the best. Headmount can also be used to put yourself into the picture. You can do both at the same time.
Here are pictures of my current set-up. Headmount modified with an additional GoPro base to attach GoPro to the back (which becomes the front). I stuff the GoPro into my Camelbak and carry it with me all the time.
I recently modified a paddle base mount (a PonoBill design) that weighs just 20 grams. Cut extra shaft in half then stick a GoPro base on it add Gorilla glue and tighten with fishing braid. Electrical tape to the shaft. This rig allows me to unclip from the headmount and then swap to the paddle mount in the ocean.
There is a tether of 100 lbs braid that I have threaded through the GoPro case (see 1st Photo). The tether goes AROUND THE SHAFT of the paddle. If the base breaks its all attached but would be dangling. This ideally provides the best of all worlds. Headmount for ease of use and low impact. Switch to paddle mount for best perspective.
I used to mount the Camera down on the blade (similar to DJ design) but you will find that the swing weight is ENORMOUS. This modified base sits further up the shaft lowerer swing weight considerably. This doesn't matter as much in smaller waves but as the waves get bigger you will not want to compromise the ability to catch waves so sliding the camera up the shaft helps significantly.