Cut larger potatoes into 1- to 2-inch chunks.
Boil potatoes in a large pot of salted water until just tender, 12 to 15 minutes.
Drain well and let steam-dry in the colander for 2 minutes.
Whisk olive oil, lemon juice, zest, Dijon, honey, garlic, 0.75 tsp salt, and pepper in a large bowl.
Add warm potatoes and toss with half the dressing. Rest 5 minutes to absorb flavors.
Fold in red onion, scallions, capers, parsley, and dill until evenly distributed.
Pour in remaining dressing and toss gently. Taste and adjust seasoning.
Serve warm, or chill 30 minutes for a brighter, firmer salad.