Of course, so much depends on your situation, whether its an adult's trip or with the kids.

All that being said, I absolutely love Maui.

Get some sushi there, somewhere yelp says is great. It's better there than here. By many miles.

Mama's Fish House is really really good food. Should be experienced once. Some would call it touristy, maybe after a couple times, but it is legitimately great food.

Road to Hana - go early or don't go. Leave the house by 6:30am. It's worth the trek at least once. It's a full day deal, and you'll be exhausted by the end of it. The thai spot mentioned by someone else is awesome! Love that spot. Also, I recommend getting a guide to go along with you, we used Shaka Guide. It's fun and super helpful.

Been to Molokini, I loved it! We went on a smaller boat to get out there quick and early. My wife on the other hand really struggled with seasickness. She didn't know she could get so sick. Proceed with caution. But I loved it haha!

Kaanapali area:
I love blackrock beach. Jumping off the rock is what I do each time to make sure "I still got it." There's always turtles there (at least when I'm there).

If you're staying in Kaanapali or thereabouts, go get a pie (or 2 or 3) from Leodas. Wonderful place. So good.

Kihei/Wailea:
Theres a big food trucks park and garden in the middle of Kihei (right next to Kihei Cafe) that has a ton of options if you have a bigger group that can't decide.

Avoids if you can:
There was massive traffic coming into Kaanapali in the afternoon just the other week. Didn't look like it was construction based, not sure where it came from. Be careful about "quick" half day trips up to the side of the island if you are staying elsewhere (kihei / wailea / etc.).