Preheat oven to 425°F (220°C) and line baking sheets.
Toss sweet potatoes, cauliflower, Brussels sprouts, and onion with oil and spices.
Spread vegetables on sheets without crowding.
Roast 15 minutes, stir, switch trays, roast 15–20 more.
Dry chickpeas, coat in oil, add for last 10 minutes.
Whisk olive oil, balsamic, honey, mustard, garlic, salt, pepper.
Layer greens, tomatoes, cucumber, cabbage in serving bowl.
Add warm roasted vegetables and chickpeas on top.
Drizzle with dressing, toss lightly or leave layered.
Finish with feta, nuts, herbs, optional cranberries.