Jim, may I suggest one more small modification to your new system?
Attach a short (2") paracord lanyard to the bottom of the sheath, and let the lanyard protrude slightly from your pocket. (Won't work well with dress pants, but with casuals, work pants and jeans, it fits.)
Then your left hand has only to grasp lanyard and pull. With practice, you can easily figure how to grasp the lanyward in a way that upon pulling up, the lanyard winds up automatically into your grip.
I say this because I use a short lanyard with my kubotan, which rides in a lower pocket, lanyard out, so that when I'm walking, my hand is at the same height as the lanyard; my hand actually brushes against it, and partially hides it if desirable, just by it's position; no contortions or unnatural positioning necessary. Since my trousers are always work variety, the lanyard is always in exactly the same place. My fingers often automatically, almost unconsciously subtlety "feel for" the lanyard when I'm walking, standing or talking with someone, but the lanyard is so unobtrusive they never notice; it looks like I'm fiddling with a strap on the trousers, which is sown on.
From there, I can have it out and in reverse hammer grip in less than half a sec, because the way that I grasp the lanyard means that when I pull up, the kutotan flips automatically into my palm and fingers close around it.
I'll bet you could work out something similar with your sheath.