Hi, Lots of posts to sort through on seats for certain!
I modified one of mine with a very high density butyl foam pad as you see in the picture. It keeps the pressure on my ischium and my pubic bone and off the tender parts (Girls have this seat issue, too). The foam is dense enough that at the most, it compresses to a thickness of about a cm.
It works for me, (female) does it look like it might help guys?
Your design looks excellent, and will be just as good for the guys as the girls. I would move the slot an inch or two toward the rear though, based on the way I sit.
I used to do this with the foam I would add to my Miyata seats before air seats came along. Two ridges to support the sit bones (probably what you said), and less pressure on the midline!
-- johnfoss - More Moab Fun
John Foss, the Uni-Cyclone "jfoss" at "unicycling.com" -- www.unicycling.com