I don't know if this would be "getting the most" out of your time there, but I would definitely take a stroll down Main St to check out the shops, then head over to Fido's for some Panty Rippers or Belikin (and the Fish 'n Chips!). Shark's Bar is a lot of fun, too ... and have some ceviche, if they have any. Oh, and talk to the Belizean people ... they are a major part of the magic of the island!!