Preheat the grill to high heat and bring a large pot of salted water to a boil for the orzo.
Cook the orzo according to package directions until al dente, drain and transfer to a large bowl.
Brush the zucchini halves and corn with olive oil and season all over with kosher salt and black pepper.
Grill the zucchini cut-side down for 5–6 minutes until charred, then flip and grill briefly until tender; place the corn on the grill and turn occasionally until evenly charred and cooked through.
While the orzo cooks or after, whisk together the champagne vinegar, lemon juice, honey, minced garlic, 1/4 teaspoon salt and 1/4 teaspoon pepper; then whisk in the 1/2 cup extra virgin olive oil in a slow stream to make the vinaigrette.
Drizzle a few tablespoons of the vinaigrette over the cooked orzo and toss to coat.
Chop the grilled zucchini into bite-sized pieces and slice the corn kernels off the cobs; add both to the orzo along with the crumbled goat cheese and chopped basil.
Drizzle with remaining dressing, toss gently to combine, taste and adjust seasoning with more salt and pepper if needed, then serve.
