Pat the shrimp dry and toss with paprika, chili powder, 1/2 teaspoon salt and 1/2 teaspoon pepper in a bowl.
Heat 1 tablespoon butter and 1 tablespoon olive oil in a large skillet over medium-high until sizzling.
Add the shrimp in a single layer and cook 2 minutes without moving, until the bottoms are seared.
Flip the shrimp, move them to the edges of the pan, add 1 tablespoon lemon juice and the minced garlic to the center, and sauté the garlic 60 seconds.
Stir the shrimp with the garlic briefly and cook just until shrimp are opaque and cooked through, about 1 minute more; transfer shrimp and juices to a plate.
Wipe the skillet if needed, then melt 1 tablespoon butter with 2 tablespoons olive oil over medium-high heat.
Add the orzo and chopped red onion and sauté 3–5 minutes, stirring, until the orzo is lightly toasted and the onion softens.
Stir in 3 1/2 cups chicken broth, 1/4 cup lemon juice, 1/4 teaspoon salt and 1/4 teaspoon pepper. If using dried herbs, add them now.
Bring to a simmer and cook 6 minutes, then stir in the sliced zucchini and halved tomatoes (and fresh herbs if using fresh), simmering another 2–4 minutes until orzo is al dente.
Stir in the olives, capers (if using), feta, sliced almonds and chopped mint until combined.
Add the cooked shrimp and any accumulated juices back into the pan, toss to combine, and taste for additional lemon, salt or pepper.