Welcome!! Congrats on deciding on a destination wedding.
There are lots of brides that get married between August and October, which is hurricane season. The one thing I suggest if going this time is to get insurance incase of a hurricane. That way you wont loose out on all your money. And also remember that August will be much hotter then October. I was married in Jamaica and really loved it. We basically considered most carribean destinations but chose Jamaica for a few reasons. First, you only need to be there 2 days to legally get married there (which we wanted to do, rather then get married at home first) and also because its an English speaking country we didnt have to pay to have our documents translated into Spanish (like we would have had to for Mexico or Dominican). We really wanted to get married in St, Lucia but it was out of our price range and needed something a bit more affordable for our guests. We really enjoyed Jamaica and will definetly go back sometime soon. We were married at the Gran Bahia Principe in Jamaica. We loved the resort (its huge!!) and had an amazing wedding. We chose this resort partly because they offered a free wedding package and have a beautiful gazebo by the ocean. We did use a travel agent to help with the planning. I was in contact with the wedding coordinators at the resort planning the wedding portion and the travel agent was there to deal with all the travel things. I don't know if going through a professional is more expensive or not, but its definetly worth it so you dont have to try to do all that travel planning on top of wedding planning. Good luck with your wedding planning!!