To make the roasted corn, heat the broiler to high. Brush the corn on all sides with olive oil and sprinkle with salt. Broil for 10-15 minutes, turning every 2-3 minutes until charred on all sides. Let cool, then strip the kernels with a serrated knife.
In a jar or bowl, combine the olive oil, white balsamic, peach preserves, all of the herbs, garlic, shallot, and a pinch of salt and pepper. Whisk or shake until emulsified. Taste and adjust salt and pepper as needed.
To a large bowl, add the quinoa, corn kernels, peaches, avocado, chickpeas, cucumber, and feta cheese. Pour over the vinaigrette and toss gently to combine. Garnish with fresh basil and more feta, as desired.
Notes
*To make vegan: Omit the feta or use a plant-based alternative.