Well it won't be Raro... A320 would have to do Aust-AKL-RAR, then overnight the crew. VANZ don't overnight due costs... so what are the chances TT would?! I would hazard a bet that VANZ crew are probably a hell of alot cheaper than Aust based TT crew.
Same with Tonga, it would have to be a return out of Aust, but then there would be no AKL-Tonga connection unless you overnight AKL. But AKL ain't cheap for overnights, almost on par with BNE cost wise.
Samoa is a closed shop with Virgin Samoa. Why would you cannibalize your own market on that route? Once biz class comes to that route, it would probably be like the old Poly days. Samoan Government very happy...
There were rumors of Jet* starting a Samoa route or RAR route.
As far as VANZ being losers in this.. the evidence does not back this up. Integrated into VAI, and the NZ bases aren't going anywhere. Business class coming to the Tasman next year. Crew numbers are stable, recruiting within the group now for replacements. Everyone going through VAI integration sim training and ground courses. No redundancies from line tech or cabin crew. Different story for management. Yes with biz class, you expect your aircraft to earn more for the outlay so marginal routes will be axed quicker. But you still need to be flying those aircraft.
Nadi services are now "full service" with a "meal" included just like Bali. VANZ might lose a few Fiji services, but I would say it's a safe bet that they do not want to pull VANZ off the routes because it competes with Fiji Airways full service product. I would expect to see TT on the SYD-NAN route to compete with Jetstar's service.
I'm also guessing to see TT Aust service the PER/DRW-SIN route connecting to the greater TT South East Asia network.
As for Palmy North / Hamilton.. who knows. Low cost worked in those places once, aka Freedom. It depends on what Uncle Koru has to say about it considering they have a 26% share and a board seat in the whole kaboole.
The Tasman though is a bloodbath. 13 odd carriers battling it out. You need to either have a really good product (Emirates, Air NZ), be real cheap (J*) or fly city pairs that have a point of difference like ZQN (Jetconnect/VANZ)