Just back from the Conrad-- Diamond status was hardly recognized safe for a black wristband. No upgrade, no late checkout. Resort was full but didn't seem that way-- there was plenty of space.
We booked all of our excursions directly through the hotel. Highlights were the catamaran with Vitamin Sea and the manta ray tour with the onsite biologist, as mentioned above.
In terms of restaurants, reservations are essential, but we were able to pester a bit via WhatsApp for better times. Iratai was a special dining experience, even dining a la carte (the prix fixes were almost always too much food for us), and Banyan was fine. The sushi place was overpriced and totally missable for us. Try your best to avoid eating at the Iratai bar-- the menu is totally disappointing.
The spa was a wonderful experience and fairly priced, highly recommend finding the time to go.
The only inconsistencies were with housekeeping, who seemed to have a different strategy for cleaning and turn down each day, and our host, who we barely saw after we arrived. We also were on our honeymoon and received no special treatment or arrival gift, so manage your expectations there.
Wi-Fi was strong in the rooms but dropped off around the resort. The TV channels are nearly all in French, so highly recommend bringing a Roku or HDMI cable if you want to watch anything in the evenings.