I concur with all the recommendations for cast iron. A well seasoned cast iron skillet will be perfect for your fish fillets (consider that restaurants use cast iron grills for cooking many things).
It involves some time but you can season new cast iron pans at home (look for instructions on the net). I’ve never tried the “pre seasoned” ones though I’m sure they are fine also, just maybe more expensive. Cast iron just gets better with use but use proper cleaning techniques so you don’t strip away the “seasoned coating”.
With that all said I needed a deep pan for big stir fry dishes and sauces. I got a Hamilton Beach 12 inch chef pan (made in the U.S.A. even) from Kitchen Collection with Eterna nonstick coating. It is less than a year old but so far is working great.
The “fear factor” about coated cook ware came from the old Teflon pans. The coating would start to slough off over time, especially if people scrubbed the pan too vigorously. The newer coatings are suppose to be safe(r), but more importantly they appear to be more durable and bonded to the base metal better so they don’t slough off. As long as the coating isn’t peeling off the inside of the pan it won’t be getting into your food.