For off the Dunedin wharf barracoutta is quite a common catch so if your using live-bait a steel trace or heavy duty mono would be the go.
What I would do is use some dead bait first ie, a pilchard from the shop or often people will lend you some fresh sprat off the wharf, if I see you down there I will be happy to , and bring some black magic sprat jigs, or the like, they are much more effective then the other brands of jigs [for instance I was there last time and caught 2 mullet, the guy next to me using black magic got 30-40], then while that bait is out there to a spot of jigging for mullet/sprat.
I don’t know about live bait rigs but one through the top lip and one lightly hooked in the tail area would work well.
Would sprat need a balloon or would a large float be fine? Someone else on the forum can answer that.
So you will need one rod for jigging [trout spinning rod is perfect] and one rod for baiting for salmon with a float, I normally rig the bait fish with 2 hooks; one in the head one down further behind the dorsal fin, and tie a few half hitches around the tail of the bait fish to hold it out, then cast it out every so often when it gets washed in.
As for a drop net there will almost always be someone else down there with a net and a willing pair of hands.