I never understood the fascination with limiting the top speed anyway.  As long as you're not approaching the structural limits of the craft, speed, altitude and horsepower are valuable insurance.  Is there ANY pilot EVER that was upset that he got above the trees sooner, or had to many options after being turned into a glider?  Setting a minimum landing speed is pure genius if the goal is to maximize safety,  but I can't fathom how limits on the other factors is anything other than bureaucratic brain freeze.
I would very much like to be enlightened on this.

Consider yourself enlightened: It's Politics As Usual, USA style. The numbers were set the way they were set to minimize the effect on existing manufacturers of light a/c & make sure that only those who couldn't otherwise fly (for Medical reasons) would find Sport Pilot privileges attractive. The existing manufacturers don't lose any existing potential revenue stream, and might even gain one if they start building their own versions of Light Sport. You can bet that they paid well to get the rules written the way they currently exist.