Soak wooden skewers in water for at least 30 minutes to prevent burning. If using metal skewers, skip this step.
In a large bowl, whisk together olive oil, balsamic vinegar, minced garlic, oregano, basil, salt, and pepper.
Add all cut vegetables to the bowl and toss gently to coat evenly with the marinade. Let sit for 15-20 minutes.
Preheat your grill to medium-high heat (around 400°F).
Thread the vegetables onto skewers, alternating colors and types for visual appeal. Leave small spaces between pieces to ensure even cooking.
Place kabobs on the preheated grill and cook for 12-15 minutes, rotating every 3-4 minutes, until vegetables are tender-crisp and show nice grill marks.
Remove from grill and let rest for 2-3 minutes before serving.