Agree, it won't be lighter. Outlaw was what... 2.4kg without the weight pockets?
My travel BPW is 2.6kg, just cant make it any lighter unless someone makes a carbon dog-bone backplate to shave another 100-150grams off the weight: 20lb tapered wing, travel XS-Scuba Alu backplate, Mares XR light harness (alu rings and gliders), plastic belt buckle and 2 small weight pockets on the cambands. The heaviest bit of the whole setup was the K-inflator and the corrugated hose, and they are already replaced with lighter versions (the X-Deep K-Inflator is lighter), I have a box of hoses and inflators and picked the lightest ones.
But hey, your approach is cool. I never suspected you could use a proprietary wing with backplate and still be comfortable with it. I am a bit puzzled about the tank instability though. If you attach it properly to the AL/Apeks griplock band and tighten the neck strap. It shouldn't move at all, at least when I tried Outlaw. I was extremely pleased how stable the whole setup is even with a steel tank, allowing me to go sideways without any movement of the rig when trying to take a photo from underneath. This is not the case with standard BP/W. They always move slightly in the chest area. I may ditch the crotch strap and use it without it, however the shoulder area is never snug and it is noticeable with a steel tank. Not an issue, but that's why I am chasing a proper chest strap to stabilize it better.
Griplock tank bands are very good, but they are a annoying to adjust when changing tank diameters, and especially difficult to adjust under water. If using only AL80, it's a dream, however here everyone is using different steel tanks.
