from my experience there are few points that will help you get a hunting action to a bait, first of all the material that you use has to be very light, so balsa would suit the purpose perfectly, secondly you have to keep everything light on the bait including the wire harness down to hooks and hook rigs.
i've found that baits that are relatively symmetrical in shape, something like rapala original is a good shape to produce the hunting action the easiest compared to others, others do work too but require a lot more tinkering.
and lastly the swimming lip your using is critical, over here in Finland trout trollers use a saddle lips to get a erratic hunting action to there baits, but others do work too like a totally round lip does produce that action too when its put in the right angle.
also you can sometimes turn normal baits into once that have a hunting action by tuning the hook eyes from the belly and from the tail end of a bait. and sometimes if you sharpen the other side of the lip to cut more water it turns the bait into a bait that has the hunting action.