Personally, I prefer condos/timeshares over hotel rooms. I've only been to Maui 3 times, so I haven't personally stayed in most of these, but here are my impressions:
Hotels
1. Hyatt Regency - love the area, love the landscaping, love the pool, love the activity center including astrology program, love that it's at the end of the road. Downside: $$$$
2. Sheraton Black Rock - smaller rooms, but awesome location. Very romantic.
3. Four Seasons Wailea - never stayed there, but it's on great Wailea Beach. It's quietly elegant and one of the few hotels in Wailea that doesn't feel overcrowded and overblown.
4. My fourth choice, the Renaissance Wailea, has been torn down to make way for a St. Regis. Grrr.
TSs/condos
1. Kaanapali Alii - if you can afford to rent an oceanfront condo, I'd choose the Alii. The condos are larger, with full kitchens, etc., it's located right on Kaanapali Beach, it has the oceanfront path for taking strolls in the morning...perfect.
2. Westin Kaanapali Villas - I own here because I love this area of Maui. It's quieter than the area south of Black Rock, but I think it's beautiful. The pools are great, the villas are roomy, they offer a complimentary shuttle to Lahaina and Whalers Village -- they did it right.
3. Polo Beach Club - These are privately owned condos which you can book through VRBO. They are right off the oceanfront path in Wailea. They are really, really nice units on a great sandy beach and the oceanfront lanais are to die for.
4. Maui Kai - I've never actually stayed here, but golly gee they have some incredible views as the building was built right ON the beach. They are very affordable compared to most. Available to rent via VRBO.
5. Kaanapali Shores - rented a private unit from VRBO here and it was awesome. The resort was smaller, more intimate and pristine. This place is much more affordable than most.