I do eat a few nasturtiums and garnish salads with them, but they're pretty spicy when the weather gets hot. I mostly enjoy them for the beautiful flowers.
I'm thankful not to have the iguanas and such here - at least not yet. They are herbivores and certainly would have a field day in my garden but thankfully we get enough cold weather (especially this year!) to drive them south. I'm prepared with a sharp shovel should I ever see one.
I only have the Geckos and Anoles, both of which eat insects, so they're very welcome, even though most of my geckos are of the Cuban variety which are an invasive species here. The native Florida anoles are a beautiful green color, but are rarely seen as they have 'migrated' upwards into the trees. The Cubans are brown camo so they survive more readily down on the ground.