Let me just say that pretty much all the dive operations have their good days and bad days.
All in all, there are many reputable dive operations here in Kona, I like the Six-Pack operations because they are much more personal, they also usually don't have six divers so in essence you could end up with what amounts to a private charter for you and your wife without the extra expense..
Wanna Dive does a cool thing where if you think you might want a 3-tank, they will do the dive as a two tank, and if your up for another dive (and you will be) it's only $45 additional and they whisk you off to another site. Their 3-tank dives are local three tanks, but that is over 10 miles of coast line, you could dive everyday for two weeks and not visit the same site twice- although you will probably want too!
I have always liked the Outrigger Keahou- they have breakfast included in the room rate and it is right next to the best snorkeling in all of Hawaii (Kahalu'u Beach)
There is also lots of shore diving along Ali'i drive. mix and match boat and shore to really enjoy yourself. Let me know if you need a shore dive guide, although most sites are very easy to navigate.
get Dick Dresie's book - "Let's Go Shore Dive'N'" Kona Hawaii for the best info.
also shorediving.com
I recommend Wanna Dive