Not that we know there is superb beach around Kuta, these beaches are where we stopped by and have fun. (just so you know). Of course, to ask which sea shine the best, bluest in color, i vote for Thailand Phi-Phi Island XD
It is pretty with the bluish and greenish hue sea color. Many many many people were sunbathing/suntanning/sun-something there laying/sleeping/reading under the hot scorching sun.
Blue Point Beach
To be honest, we had the most unpleasant experience here in blue point beach. The thing is, we were trying to take some photos of how romantic this place is, with the sun and sea and beach. Guess what, we were chased out by a the worker there because we were not supposed to take photos unless we buy meal there. They said they have the best sunset view there though.