First, prepare the dressing. In a small bowl, whisk together the lime juice, honey, salt, and pepper. Gradually whisk in the olive oil until the dressing is well combined. Set it aside.
In a large bowl, combine the arugula, watermelon cubes, cherry tomatoes, thinly sliced shallots, and shaved fennel.
Drizzle the salad with the lime-honey dressing, and gently toss to ensure that everything is well coated.
Sprinkle the crumbled feta cheese over the salad.
Tear the remaining fresh basil leaves and sprinkle them over the top of the salad for an extra burst of flavor.
Serve immediately, and enjoy this light and refreshing salad!