The big advantage of braid is that it is going to sink much faster than mono. Therefore you will need a lighter jig head than you would with monofilament. I’d use a rod length or so of mono for a leader. Nowadays I see anglers fishing for sea-run brown trout at river mouths with all manner of soft and hard bodied lures where once everyone fished with feathered lures or small metal spoons. These lures certainly catch sea-runs. I suspect that some methods of fishing soft baits for sea-run trout will be more effective than others. For example feathered lures like Hopes or Yellow-Rabbits are always cast across fast water and retrieved. Perhaps it’s possible to drift fish soft-bait minnows, that might represent a silvery, downstream effectively, or a combination of drift and retrieve, in the right water?