My wife is similar, but 4" shorter, long torso, shorter legs. She tried several BCs, nothing fit her, she always felt like she was swimming around inside her BC. She has a DiveRite steel backplate with Transplate harness, size medium. She loves it and won't dive with anything else. I picked up a "Lite" DiveRite steel backplate for warm water tropical diving from someone here on Scubaboard, with an extra large Transplate harness (bigger guy, but he couldn't get it adjusted correctly). It took me about half an hour of adjusting so it fit exactly like her medium size harness (no need to cut 2" webbing), and my wife can't tell the difference between the two (extra large has longer shoulder pads). Manufacturer specs are just rough guidelines, but I would bet the Transplate harness will fit you once it's adjusted
For continuous webbing, I was told crossing the straps behind your shoulder works well for smaller people. When I took an advanced wreck class last year, my instructor (big guy) encouraged everyone to set up their harnesses that way, since it keeps the backplate sitting better on your back. I don't know about that, but it's definitely more comfortable and fits better. I haven't tried setting up a Transplate harness with the straps crossed behind the shoulders, but don't see any reason why it wouldn't work and be comfortable. The nice thing about backplates is you can try things and make adjustments to get it to fit you exactly right
Please let us know what you end up with and how it works out