Hi ,
I have completed the trip from Phuket to east coast several times and a diferent route each time ,

love the place ,
where is your departure point? maybe I can give you some tips ,but timing is everything if you are heading east as the prevailing winds are from the east and the cyclone season is no time to be caught in the eastern islands .
For other times of the year ,take plenty of fuel as it is light in the Java sea with only the odd westerly gale ,and even then it will not blow as far as the Banda sea .

cu