Lauri -
I think you have the right attitude :p With that frame of mind, you will have a WONDERFUL time in Belize. Things don't always go exactly as planned - and that can apply to any airline or restaurant or anything else for that matter. I can tell you are the type to go with the flow and that's the best attitude to take to Belize.
I honestly would not worry at all about your flight. We felt we were in good hands with TACA. Have a GREAT time on your trip - and be sure and let us all know how it went afterwards.