I dove with Lahaina Divers this past Feb and would dive with them again. My buddy did her check-out dives with them, so my dives were a combination of fun dives for me (solo), and "easy" dives for her (new buddy!). The afternoon dives seemed to be more full than the morning dives, with more "newbie" divers in the afternoons. Never felt crowded or packed in on the morning dives, plus the SI snacks were better!
There is a discount (or there was when I went) for multi-day dives (I booked over the phone), so my prices (2-tank dives) ranged from $72 (Turtle Reef) - $175 (Molokai).
It was an early morning and a long-ish boat ride to Molokini, but saw a good variety of fish at the Crater. A storm rolled in while we were there (and cancelled a few of my dives later in the week) so instead of a second dive in the Crater, we moved closer to shore and dove the Pali Coast, which was probably one of my favorite sites due to the sheer number of fish/varieties of fish there! The Backwall had lots of cool critters (nudibranchs!!, GIANT lobsters, frogfish, white tip sharks). Not sure of the comfort level of your group, but there was a decent current when I was there, and it's really easy to go deep (though that's where the big stuff is!).
My Turtle Reef dive was at Mala Wharf, which you can also do as a shore dive (there's actually a lot of shore dives in the area- Lahaina Divers has a helpful map you can pick up at their store. If I can find mine, I'll scan it and send it your way). Lots of turtles there, but also sharks sleeping under ledges, several varieties of shrimp, an octopus and NUDIBRANCHS!! (my favorite!). A Hawaiian monk seal showed up for our surface interval, so I jumped back in with my snorkel and watched him (her?) dive down and around the concrete structures for a while- that was pretty cool to see!
Did a trip out to Lanai and dove the cathedrals- lava tube swim-throughs- and that was pretty neat. A bit of a surge going through some of them, but some really different topography. Also found some nudibranchs I hadn't seen, so that was awesome!
The trip out to Molokai was... sporty? Crossing the channel was seriously choppy. The boat was pretty quiet, both going out and coming back, a few people got sick, but once we were through and closer to the island, things calmed down a bit. Getting back on the boat, the ladder pitched up and down quite a bit, but slowly enough that you could time your exit. Saw 3 hammerheads (including one that joined us for our safety stop! ...after I had turned off my camera
got a shot of him swimming away). We checked out a reef on the first dive and saw a few fish, but it was mostly a drift-along-in-the-blue-and-hope-to-see-something kind of dive. We saw sharks, but not til the end of the dive.
I was there in Feb and saw more whales on my dive boats than on the whale watching cruise we did- we even had a mom and baby pass about 10 feet off the stern as we were getting ready to head back to shore! You'll likely see/hear them while you're there as well!