Hi mate,
Mirroring what Muppet has said, i've had some luck on big paddle tails cast around marker buoys down our way. They have a weight integrated into the body of the softbait, and a great wobbling action.
I gave it a try after reading an article by a kingie specialist in Australia who swears by that method, as opposed to top water lures. He uses Storm Wild Eye Shads, and Bozos. They are about 7". I brought in some very similar Tsunami shads from the US which look great, but haven't tried them yet.
The likes of Uncle on this forum used to swear by the Slug-gos in 7" or larger. Coincidentally a thread on Slug-gos was revived yesterday on the for sale forum. They look similar to the long pink lure DV was using in the image above.
if you go on YouTube, there are some good videos of guys catching kingies in deep water in Australia on big Z Mans - 7-8" jerk shads. Using basically a mechanical jig motion.
And speaking of Z Mans, kayak expert and writer Stephen Tapp gave a talk at the Auckland On Water Boat Show last year and showed off a rig he uses for top water kingies - 8" Z Man Mag Swimz paddle tails which he casts unweighted in the same situation that most people would use stick baits. I got mine from the US in some nice piper/baitfish colours.
As an aside, you might like to try sinking stick baits, if you haven't already. They are quite forgiving in terms of technique, and have great actions just below the surface with a bit of a twitchy retrieve. Or maybe one of the bibbed Rapalas - X Rap. Again, you don't have to do much except retrieve.
I rig my lures with a Rapala loop knot, supposedly gives a nice action.
Good luck.