In a small bowl, combine thyme, lemon zest, salt, and pepper. Sprinkle over fish, and let stand for 10 minutes.
In a large stainless steel skillet, heat unsalted butter and 3 tablespoons oil over medium-high heat. Cook, stirring constantly, until butter is melted and hot. Add fish, and cook until center of fish flakes easily with a fork, 2 to 3 minutes per side. Keep warm.
Sprinkle shrimp with blackened seasoning. In a large stainless steel skillet, heat 2 tablespoons oil over medium heat. Add shrimp, and cook until pink and firm, about 2 minutes per side. Set aside.
Add remaining 2 tablespoons oil to skillet. Add shallot, and cook, stirring constantly, until tender, 1 to 2 minutes. Add wine, and cook until reduced to ¼ cup. Add cream and salted butter, and cook, stirring occasionally, until thickened. Add Parmesan, and stir until smooth. Add crawfish and shrimp; cook until heated through. Serve over cooked pasta with fish. Garnish with thyme, basil, rosemary, and lemon wedges, if desired.