After tearing up my alpha pads for HE-500 science (did most jergpad mods besides velour overlay), I'm beginning to think the Audeze vegan/micro suede pads might be an ideal candidate in what I'm looking for. The alpha pads brought a much more open, wider sound and much more comfort vs the jergpads. However, I found they greatly benefited from me cutting slits on the outside of the pads and where the pads meet the head. I believe there was a noticeable improvement in filling out a dip that existing around 7-8KHz before I cut those slits. For reference, I had already cut holes in the bottom of the alpha pads, and I did not try cutting slits in the inner part of the pads.
With the Audeze vegan pads, I'm assuming the micro suede material will be more porous and thus make up for having to cut openings in material such as leather or pleather. With that and their similar shape, I'm thinking they'd be a good candidate for replacement pads. I'd still likely do the holes in the bottom, though the shape of the pads may negate the need of back vents.
I've also noticed that the alpha pads seem to have a lighter sound to them. My best guess is that they have more of a roll-off in the bass. I read elsewhere that the Audeze pads can benefit from having two plastic rings in place (stock and HFM mounting ring) for better bass conduction. I'm wondering if I'm seeing a similar effect here, as the alpha pads I have are perhaps a tiny bit loose on the mounting ring and headphone overall. It might benefit from a different mounting method. For example, I've seen someone directly tape their vegan Audeze pads to the headphone and skip the mounting ring entirely. That's one big thing I'll have to consider and play around with on both the alpha pads and if I decide to try those vegan pads.