I was down in Belize last winter, and I know how hot it is. If Jeff was currently making taking kilt orders I would suggest a Pittsburgh kilt. They would be great, because if you lost weight you could just move the hook fasteners.

But since he's not taking orders right now, besides the Utilikilt, there are Freedom Kilts, Amerikilts, the canvas Buzz Kidder kilts. Any of these would work for you.