When I grill fish, I use really good olive oil, salt and pepper, and when something like Meyer lemon is in season, I love peeling the entire Meyer lemon, juicing it over the top, or even taking the zest of the lemon, soaking it in a little chile water, a little Thai chile water, and then putting it on top, and it adds a really good heat. Awesome flavor. You can keep the salt count low because you had all the citrus and the heat. That's a great trick. That's what I love to do.