Tag for info. I just did the exact same thing you did, today. I put my new padded VCAS and triglide on my rifle and had the same issues with length you did. I took the quick release buckle off, and the length was better but not perfect, and I want to keep the quick release buckle as well.
I don't know where you put your triglide, but there were two buckles on the short strap meant for the rear of the weapon. I replaced the top buckle with the triglide, first with the QD point facing towards my body, then I tried it with the QD point facing away. Facing towards me, there were only a few positions in which I even noticed it was there at all in two point mode. Facing out from me, it suddenly became all kinds of uncomfortable. Like jammed into my face when shouldering the rifle and pointing NTCH.
On the way to work tonight I thought about moving the triglide down to replace the bottom buckle, just before the sling threads through the QD swivel. That should remove it from the equation entirely as far as having it press against parts of my body, and may improve the length issue, maybe enough to add the quick release buckle back on.
I think we both may be boned on getting it any tighter, simply because the padded version just doesn't have enough adjustable length to fit all types. If we can't find an acceptable solution I'll probably just toss it on the EE and get the non-padded version.