I use the butterfly D-ring on the crotch strap. Works well for me, since I have rather short arms. I can reach that. The Butt plates I have used, tend hang too low from me to be able to easily reach. All’s I used for the valve loops is a loop of thick bungee bungee run through a small quick link that goes through a hole, high up on my backplate. The bungee loop knot catches in the quick link to hold it in place. I just stretch the loop over the cylinder valve handle & it snugs it up right under my arm pits. Works perfectly. My wing is now a triangular Hollis SMS75 wing that is bungee’d at the top & free at the bottom. Changing this, allowed me to drop from 10 lbs of trim weight that was in pockets high up on my shoulders, down to 4 lbs to trim out perfectly with 2 AL 80 bailouts. The lift in the rear, is just what I needed (& I bet cheaper than the Halcyon).