Mike,
If you want detailed information about the Mississippi barrier islands, pickup a copy of Scott William's book, "Exploring Coastal Mississippi." Its available from Amazon in soft cover or kindle editions. The book was published in 2004; therefore, the landscape has somewhat changed because of Katrina and time, but remains pertinent. Williams is both a sea kayaker and sailor, he writes about each island based on his personal research and experiences. I don't think that there are any other publications (on the market) that come close to the detail that he presents. There are no maps, charts, or diagrams in the book; however, he does reference the charts that are appropriate for each island. Well worth the read and will give you a "lay of the land" before you get to the coast. Again just be aware, that there are new marinas as well as major modifications to all marinas post Katrina. You are going to have to pick and choose the areas that you want to sail because there's way too much territory to cover between the Mississippi coast and Florida pan handle on weekends over a 90 day period.
Rick's suggestion to bottom paint and keep your boat in a marina is a great idea. Most of the marina's on the Mississippi coast would be $200 per month or less for your boat and you might possibly get a military discount. As Kloudie & JO mentioned, definitely take the boat to NAS Pensacola and explore Pensacola Bay, Santa Rosa Sound, Big Lagoon, etc. The Florida / Alabama coast is a beautiful area to sail with lots of anchorages. NAS Pensacola is only 2 and 1/2 hours via I-10; easy trip and worth the ride. Have Fun and GO Navy!!