I'm heading to Barbados for 3 weeks in March ,
only an 8hr flight from London, the wind stats are as good as i could find anywhere. never been but from what I've heard the night life should be ok, hope so.
playa del carmen or cancun are great for nightlife specially in March (spring break) but not as windy as i would have liked last time i was there in March. Isla Blanca has more wind than playa.
Jamaica is good depending on what kind of night life u are looking for. wind is definitely good.
Grand Cayman, Saint Martin, Aruba all got good winds and decent night life.
Sicily is good if you rent a car u can drive to the kite spots and stay in the cities or vice-versa. people should be starting to get into the summer mood and coming out a bit more
need a wet suit this time of year. night life more fun if you speak Italian.
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Never been but Cape Verde was another place i was strongly considering this year but Barbados just got it for me.
good luck hopefully that gives u some food for thought.