My wife has really enjoyed switching from jacket style to back-inflated BC's. We both have our original low-bucks warm-water only BC's (hers an Ocean Edge Tek-Vest and mine a Seaquest Explorer), but we changed to Dive Rite TransPac II's. We have weight integration now among other things in our harness style BC's, and the modularity is appealing to both of us (we're both engineers too, and I'm a bit of a gadget guy . . . my syndrome probably sounds familiar to someone else out there . . . :54: ).
Anyway, you may want to test-fit a modular style harness or two, especially if you plan on either doing some cold water as well as warm water diving, so you can change air cells easily, or if you think your diving might enter the realm of multiple tanks some day. There's several brands (Dive Rite, OMS, and Scubapro to name three quickly).
My wife is about your same height and weight, and uses a XS TransPac II harness with the older Junior Wings (current equivalent is the Trek wing), but we both have several "wings" depending on what we plan to do on a particuylar vacation / dive trip.
Often, dive shops will have a fairly diverse stock of rental equipment, so you may want to negotiate a 'test drive" with several models in their pool or something, after you've narrowed down which ones seem best to you above water.