Since your'e a scientific diver you can probably find at least 10 people who can help you perfectly dial in a continuous webbing harness. And as I found through multiple iterations of adjustable shoulder straps and belt sliders, a well-adjusted fixed harness works great- and as a bonus it's going to be your least expensive option (or you could go down my path, where you start with the most expensive harness and keep spending money changing it until you land on the cheapest setup.) We're currently switching my wire's backplate out to a Subgravity short plate. She's taller than you, but has a pretty short torso, and ends up with her standard size plate resting on her hips more than it should