I have had good luck with java fern in low level brackish water, at least until my fish bit a zillion little holes in them. My tank was littered with java fern confetti... But this was with GSP's. They grew well. Now that tank is saltwater so I don't have any plants other than a couple Marimo moss balls. Those will do great in brackish water. As for driftwood, it will work but keep a good eye on it as the salt will lead to it deteriorating faster than it would in freshwater. If the salt level is low I wouldn't really worry about it.