Hi Sammy,
This is just my opinion...I really think you should pack the barrel for the six months. Honestly, you will save yourself so much time and money. No Frills and Freshco are having some amazing sales right now. Filling the barrel with dried goods (pasta, corn beef, tuna, Ragu, shampoo, soap, body wash etc.) will be so useful. I find certain foods are cheap in Jamaica but a lot of the food we like Western stuff are extra pricey.
Besides you do not know how much diapers, formula and baby wipes you'll need. As your princess gets bigger she'll be using more stuff. The 3 checked bags seem like a lot but once you start packing they will fill up so quickly.
Again just my opinion. Have fun at the pool