Just spent 10 days in Bali.Wind every afternoon between 12 and 18 knts. Had a 13m.Dont bother less than 12m.Sanur is the place, flat lagoon + waves on reefs, very safe.Nosa Dua also good.All East coast.Make sure you go in high tide.West coast, Kuta/Legian etc not kitable but good surfing. Enjoy.
if you can manage it take both. last year i used my 12 four or five times in two weeks. 14 for the other days. i'm heading over monday for three weeks, cya there!