I really enjoyed the Wailea luau. It was the only one I've been to, though, so I'm not sure how it compares. The beach faces west, so you get to see the sunset and the show spans both daylight and nighttime. You can also see the misty island mountain (forget the name) that they talk about during the show. I'm traveling now, but can post some pictures when I get home this weekend.
You want a good luau and traditional at best, then try the one at the PCC. PCC is located on the North Shore and the island famous Ali’i Lu’au.
Here is the site to learn more about this luau: http://www.polynesia.com/alii-luau/index.html
From living there in Hawai'i and cooking luau myself, the best is at the PCC. You will enjoy the entire package and I strongly recommend that you spend a day AND the night at the PCC to enjoy the true polynesian cultural. Food is a MAJOR part of this experience and you will enjoy the entire package. Well worth the trip and the PCC is talked about all the time, as it is the #1 destirnation in Hawai'i.
Congrats on your upcoming wedding.
Since you are staying at the Ihilani, I would go to the luau @ Marriott's Ko Olina's Vacation Club 2 lagoons down. I have been to the luau @ the PCC mentioned & then the one @ the Ko Olina & enjoyed the Ko Olina much more! And you can walk to it! Enjoy your honeymoon. The Ihilani is wonderful. I have stayed there as well. You will love the lagoons & area.
The Old Lahaina Luau in Lahaina is one of the best on Maui. If you are staying at the Wailea Marriott it's about a 25-30 minute drive north to Lahaina.