I tried the tape around the pads idea, not so much with the G-cush salad bowls as with the L-cush doughnuts. I got more bass but the result sounded muddier, sort of like listening to a Bose product. I didn't like it.
I did, however, end up slicing off a few millimeters to bring the ears closer to the driver. My fear was that in doing this, I'd just end up where I was with the doughnuts. But the wider aperture of the G-cush pads actually allowed better HF dispersion. It's my contention that, for an unamped experience, increasing the ear/driver distance while widening the pad is overkill. On even my GS-1000, the sound got too sweet it felt sibilant. I hated it. When I told others, they said I needed to burn my GS-1000s in. Then they told me that I had to break my pads in, through such things as washing them, squishing them, bending them, et cetera, until they became so soft that they squished together more readily. It didn't take long for me to realize they were advocating some form of compression back towards that driver that had been distanced by the new pads.
So, one day when I got the nerve, I cut a few millimeters off of the front of the pads. it worked wonders. The bass came back while the benefits of that wider mouth still gave me a lot more HF presence than I'd had with the doughnuts. My GS-1000s finally sounded as great as people were telling me they could. It impressed me so much that I took the same set of scissors to a spare pad, which I applied to my SR-60. The SR-60 didn't have the depth of bass you'd get out of a GS-1000 but it was still quite impressive, especially while grabbing all that fresh HF from the wider aperture of the cushion's mouth.
I've talked about this before, so I won't clutter up your thread with it. If you get curious, I have pics over at my albums. Disregard the ugly guy in the picture. That's me.