Hi Gerhard,
I'll chime in here with some tips that I've found fishing Vanuatu and also having intel from Ocean Blue guides and team.
Firstly - its the hardest place I've fished to pack for, so many variables to cover from heavy to light tackle, inshore, reef and offshore.
Second - Expect to encounter dogtooth, as far as numbers & size due to deep water with structure so abundant. Landing them is your issue.
Vanuatu islands are remnants of volcanoes, a few are still active. It's quite common to fish areas only a hundred or so meters out from a steep island or towering rock face. These waters you can cast poppers into shore breaks, and jig 150g at the same time! Or throw a 5-7inch soft plastic on 5/8th jig head for smaller reefies.
For days with a jigging bias, most drifts would find you starting in 30m and drifting out 90 odd meters but plenty of 100 - 150m areas if you are so inclined.
We stopped on the deep side of Monument rock one time (similar to Lord Howe's Balls Pyramid) one glassy calm day and fished barely meters from the vertical rock face. I was nervous we'd crash into the thing, I could have easily tossed a rock and hit it. Depth was 60 meters & Andrea was trying to find a place shallow enough to jig in!
The guys on boat 2 jigged a solid sailfish same place (1st drop) next morning.
For days with a casting bias,
There are areas that are solely for popping, shallow, nastier terrain, reefs. So hours of casting working along the washes of islands and some reefs. The GT's are there, some very big fish too. Like anywhere, lure presentation needs to be on point. There is a reason why the more experienced anglers are the ones holding the big 40kg GT's in photo's.
There are islands with fringing reefs, shallow flats and passages, but most islands are steep & predators come in close.
Pack broad but not deep - terrain is quite kind as far as losing surface lures. Maybe 5 large poppers, same of stickbaits. then medium sized about half dozen or so for inshore and offshore too. If you are hardcore for GT's & dogtooth on surface only, then obviously pack more.
Cover floating/sinking stickbaits and chuggers and maybe a pencil etc. I like Hammerhead Tobi 123, Pete Morris has done great with Heru Skipjack (size?) for a number of solid GT's & dogtooth.
Take some surface lures for bluewater species. YFT, mahi mahi and wahoo.
The guys have been getting marlin also on poppers, so rig with assists offshore. They landed, released one about 130kg blue on saturday (Halco Haymaker) see photo's if you're on Facebook.
YFT also, for offshore on poppers/stickbaits but also the small jigs.
As for jigs, doggies like small ones cranked fast. I've caught them on my light rod (Saltiga 63s) up to 15kg, using 60g jigs aswell as soft plastics.
So must haves are:
6 or so jigs from 60-130g.
Then about 6-8 from 130-250g for larger dogtooth on your heavy gear. If you want to target big doggies in deep water, take a couple 300g plus.
We also get AJ's and ruby snapper / puka puka in deep deep areas.
Jigging Master Fallings Special in 190 & 260g work very well.
I'm over there again soon, mainly taking photo's though taking a new 65lb setup for dogtooth on a 'medium' rated Patriot Design jig rod.
I'm like you, I go for catching & having fun - not kg's. There are more mid sized fish in the food pyramid than apex predators. I enjoy medium tackle, plus the lighter gear always produces even if the heavy stuff is slow. Previous groups have commented on this, expecting only to target fish like the photo's on the website but having fun casting to small tuna, micro jigging etc.
Others will be able to add their 2c worth and own experiences.
Cheers Dave