There are two different reactions that people have when someone suggests that they might want to write their own wedding vows: either they think it's the best idea they've ever heard, or they think it's ridiculous. Why try to improve on what's already out there? Standard wedding vows can actually be lovely, and they certainly get the job done, but writing your own vows really, truly personalizes your ceremony. Since you're already flouting convention and having a destination wedding, why not try something new with your vows?