Prep your produce. Wash and chop everything first.
Shred the cabbage, slice onions thin, halve tomatoes, and dice cucumbers. This makes assembly fast.
Make the slaw dressing. Whisk mayo, vinegar, Dijon, sugar, salt, and pepper. Toss with cabbage, carrots, and red onion.
Chill for at least 30 minutes so it softens and flavors meld.
Boil the potatoes. Add halved red potatoes to salted cold water. Bring to a boil and cook until just tender, about 12–15 minutes. Drain and let steam-dry for better texture.
Whisk the vinaigrette. Combine olive oil, Dijon, white wine vinegar, honey, salt, and pepper.
Toss with warm potatoes, then fold in celery, green onions, capers, and herbs. Taste and adjust salt.
Stir the chili-lime butter. Mix softened butter with chili powder, smoked paprika, lime zest, lime juice, and salt. Set aside.
Grill the corn. Heat grill to medium-high.
Grill corn, turning every 2–3 minutes, until lightly charred, about 8–10 minutes. Brush with chili-lime butter and finish with cilantro if you like.
Build the tomato-cucumber salad. Whisk olive oil, red wine vinegar, garlic, oregano, salt, and pepper. Toss with tomatoes, cucumber, and onion.
Add feta and herbs just before serving.
Taste and finish. Adjust acid, salt, and heat across dishes. A squeeze of lemon or a pinch of salt can brighten everything at the end.