We spent 12 nights at Kapalua in June. I had originally planned on booking a garden view room, but found that if you book a partial ocean view, you get a free night for every 5 nights booked (which is why we stayed 12 nights). A partial ocean view also gets you 2 free breakfast buffets a day. I decided to go for the partial ocean view to get the benefits, and they were definitely worth it. We had the breakfast buffet around 9:00 or so, and then usually ate only one additional meal each day. My food costs were way less than I had anticipated. We went to quite a few "local joints". Since you refer to night life, I'm assuming you won't have kids with you. For those that do, something I didn't know before I went is that kids eat free at breakfast and lunch. That saved us a bundle. When we got there, they upgraded us to an ocean view without being asked. We absolutely loved this hotel, and after visiting several other high end hotels, couldn't wait to get back to our place.
Having young children, we really weren't interested in the night life. But Lahaina, the "tourist town" with loads of shops and restaurants, is only about 15 minutes or so down the road. I don't know what the night life is like there, but I think it would be the only possibility in the area. There is also a strip of hotels (Sheraton, Westin and others) about 10 minutes down the road at Kaanapoli that might have some night life things going on.
We did two things kind of out of the ordinary. On our second day there, we did a snorkling trip with Ann Fielding, a local marine biologist that took us to the prime snorkling area and then to a place where they had sea turtles. She spent time with the kids, educating both them and us about the various marine life we would be seeing while snorkling. It was a very good experience. We had reserved a snorkel trip to Molokini that everyone talked about, but the snorkling at Kapalua is extraordinary, and many people who took the boat trip said people were getting seasick and that they didn't see as much there as they did right on the Kapalua beach. We cancelled the boat trip. The other thing we did was to rent a local guide to drive our car on the Hana road. I wanted to do it, but didn't want to drive myself, and after doing some research, didn't want to do the typical guided tour thing. This was also a great experience (aside from the fact that we went on a rainy day). I could enjoy all the sights, and she custom designed the trip to suit our interests and what we wanted to do (ie. not spend too much time in the car). She took us to some off-road places that most people don't know about. It was definitely something I'd do again.
I am in the process of typing up a very very lengthy and detailed trip report. It's much too long to post here, but if you're interested, e-mail me and I'll send it when I finish, which should be by the end of next week.