Caribbean group trip

Hi all - thinking to book a trip in December. We are 8 adults in our 30s. Was thinking to book Anguilla and St barths for a 7 night vacation. Has anyone done this? Any recommendations?

Based on my research within this reddit page it seems FS is the best option for Anguilla - and possibly Eden Roc or Le Barthelemy being best for sb. Just curious how these two islands would work for our trip or if there's a better combo? The concept is to have a luxurious relaxing vacation with some sports/activities - and then finish off with some lively party action.