Seafood Tower and a little foie?
Or perhaps a nice cozy place (nothing fancy shmancy) for a seafood tower and some foie gras?
For seafood platters, I'd go to a larger brasserie like La Coupole (14th arr.) or La Rotonde (6th arr.) in the south of the Luxembourg Gardens, both M°: Vavin. La Rotonde, smaller and cozier, has also a decent foie gras on its menu. The other Flo Brasseries are an option as well.