Hi Ray,
At least the way I understand loops, you can't change the impedance ratio unless you change the turns ratio. But certainly by reducing the pickup loop coupling you're improving the loop Q; you're just not doing it by changing the impedance ratio! Anything you do to reduce pickup loop coupling will move toward unloaded max Q of the main loop. Of course you eventually reach a point where you don't have enough signal in the pickup loop. Most folks change the coupling by varying the horizontal distance of the pickup loop from the main loop, usually by making the main loop wider so the pickup loop can be spaced farther from the main loop, with the pickup loop the same size as the main loop. But your way of doing it with a smaller loop will certainly work as you've obviously figured out how to physically mount the pickup loop.

Best regards,
Steve