FP diving is quite diverse - from Tahiti where all international flights arrive I first bought an inter island pass and flew Tahiti - Bora Bora - Rangiroa - Tahiti - Moorea and due to a plane losing an engine didn't get the Tahiti - Fakarava - Tahiti leg in. Having booked inter island passes several times since I've worked out you need to head east from Tahiti and do the Tuomotos - Rangiroa and Fakarava where the diving is IMO some of the worlds best. Fakarava keeps eluding me in scuba but it is a soft coral biodiversity hotspot with the sweet spots being the north and south passes although they are quite far apart so hoping someone with recent Fakarava experience will help out. Friends I've booked for have opted to dive with Fakarava Spirit or Fakarava Diving Centre and do the north and south passes on seperate days.
Fakarava is also full of sharks

Rangiroa - Tipuata Pass is the must do dive. I highly recommend Rangiroa Plongee and stay at Pension Tiena and Marie - Polynesian hospitality just a short walk from the dive centre and lili cafe - you really have to eat Mahe Mahe in Vanilla Sauce and poisson cru there. Diving the pass is high voltage high current. If you are not super comfy with negative entries there is the second largest lagoon in the world to dive in....and that's full of sharks too

I keep meaning to get to the other pass but have had so much fun at Tipuata it's a "on the list". Dolphins are pretty much present 1/3 dives, variety of sharks, seasonal hammerhead mating aggregation, seasonal whales...it's an amazing place to dive. I haven't heard anyone rave enough about Tikehau to bother.
From the Tuomotos you need to fly west to the societies - Bora Bora and nearby Raitia - although depending on the day of the week you may need to go back to Tahiti before going to Bora Bora. Diving at Bora Bora is so so...lemonsharks and rays that are pretty conditioned to the boats engines due to years of fed dives from the giant chain op all through FP. There a manta dive - a manta showed up, I dived, half a cruise ship dived to see the one manta that turned up. Try and schedule your diving when there is no cruise ships in - Eleuthera would be my choice but unfortunately I had to dive with the other op as taking a single diver out was not feasible. Raitia I haven't heard any rave reviews about diving but it's a pretty Island if you choose to go there.
You then need to fly back to Tahiti unless they've added a BB - Moorea flight but once in Tahiti you can get in a dive - there's a nice enough wreck and again at the right time of the year the Tahiti express is a kick ass drift dive. From Tahiti take the ferry across the sea of the moon (about an hour, ridiculous to pay for a ten minute flight) to Moorea where there is some pretty diving with a lot less current. Whales often play just offshore during Jul - November. Moorea Blue at the Moorea Pearl resort were very good.
Lining up the flights is sometimes the hardest part - have fun. You may also like to check out 6 passengers diving who get a good wrap from posters here who have dived with them. Diving is out of RIBs backwards roll entry everywhere other than BB that I have used. There is no elegant way to get back in a RIB