Been going here for 20 years. The best diving on Efate is accessed from here - Hat Island and behind Miso are favourites. Schools of eagle rays, blacktip sharks, caves full of crayfish & the occasional hammerhead. There are some hotwater vents behing Miso too. The housereef right off the beach is nice too.
Shore dive not far out of Luganville. This is the place where the US bulldozed all their equipment after WW2 - trucks, jeeps & all kinds of building materials all melded together after 70 years underwater. Good snorkeling site as well as divng to about 20m max.
The Konanda (not Konandra) is an inter island trader purpose- sunk for diving in the last few years, a couple of hundred meters behind Ifira island. It has little growth on it but is a good are k for swim throughs, and at a max of 25m you get plenty time on it. Good for photography, and via usually 15-20m. Regular trips by Big Blue and Nautilus dive shops.