So, very rudimentary and preliminary test result here; I grabbed that thin mousepad that I have, simply flipped it upside down so the grip side was up, placed my mouse on it and glided it around on the desktop... It's literally perfect; quiet and smooth with the exact same feel as the mouse on the pad normally. I'm gonna cut some strips off it today and glue them to the bottom of the mouse and see if that bit of extra height off the table top interferes with the laser's accuracy.

[EDIT] The mouse works 100% fine with the cut mousepad underneath. I cut a hole for the laser to shine through and then trimmed the sides to conform to the general footprint of the mouse and its working great. Once I trim the excess pad from the edges and from the underside of the mouse (the current default skates protrude a bit from the bottom of the mouse), the pad will only be in contact with the desk surface where the skates are, further reducing friction and inertia. At the moment with all the excess pad material, I'd say it's off from my ideal resistance and weight by maybe 20%. I think once all that is cleaned up, it's gonna be pretty ideal.