We also stayed at the Marriott Waikiki Beach. We loved it. As mentioned, it is directly across the street from the beach like many of the hotels are. It was a good price point for us and the rooms were recently renovated. It was very close to a Waikiki Trolley stop which we used, and also had a tour lobby which was great because we did two organized tours during our Waikiki stay (Diamond Head and Pearl Harbor). We also felt it was centrally located for walking to shops and restaurants. Directly across the street at the Aston there was a Wolfgang Puck Express, just like the one at Disney Springs, so we ate a couple quick meals there as well. And there was an ABC convenience store directly in front of the hotel.
We spent 3 nights in Waikiki and later 6 nights at Aulani. We opted not to spend a beach or pool day in Waikiki. First, there were very few hotel pools in Waikiki that are worthwhile IMO. And also because we found Waikiki beach to be very crowded and not so enjoyable. We used this time to do the tours, shopping, and "night life". Once we got to Aulani, we spent more time relaxing and seeing other parts of the island. This strategy worked well for us. I'll also caution about Hilton Hawaiian Village in Waikiki - I almost booked it because it felt like more of a resort than the Marriott did. But after seeing it in person, it was a good walk to the heart of the strip so it didn't seem to be a great location.