I don't think you should let the fact that it is 'only £6 more expensive' per night put you off staying at Sugar Beach!
My sister-in-law was married there this time last year and it was absolutely beautiful. Though I didn't stay there myself, she and her husband spent their honeymoon at the hotel and had nothing but praise for the wonderful food and service etc.
The actual wedding was a magical day with the ceremony taking place under a beautiful marquee on the grounds right near the beach, and evening dinner was held in a very grand hall, with the catering cooking outside on wonderful barbeques etc... I'm quite sure you will have a wonderful day so don't be put off!
Have a great time