Hello, Dazling here. I made a video recently where I ran Saltmarsh Wilderness 100 times and logged what I got, then did the math on it to determine the drop rates, average amount of stuff per run and chest, etc, as well as looking at some good routes for running the slayer zone. Here's the video and the spreadsheet for anyone to peruse, feel free and let me know if it ends up being helpful and/or informative!
Spreadsheet: 100 Runs Saltmarsh Wilderness