When you are going makes a big difference. I suppose that since you mention the FF boat in dry dock you are talking about the near future. FF was recommended for shore diving Tunnels and my memory is you could easily do 4 different cavern dives there with the right guide. I could be wrong but there is an long inner reef, then an outer reef with both inner and outer walls, all riddled with holes like swiss cheese. If there were only 3 dives there, there is also a dive on the far side of the dry cave. Or you could make one trip to Tunnels morning and another dusk/night. If the conditions were right, I'd do that.
Conditions are a big issue; whoever you book with should be going to the best conditions if one side of the island is crappy. Don't get locked into one side or the other, make sure the op wants to give you the best diving for the day, not for their bottom line.