lol....you wanna provide use with dual layer dvdrs?
Those are still quite expensive and ther are people still w/o dvd burners, but definitly those will come later
If you shop around you can find dual layer disks fairly cheap. A few weeks ago I saw a pack of 25 on tigerdirect for less than $2/disk Canadian. Granted, that might seem expensive compared to $0.50 or so Canadian for single layer disks, ...
BTW. In regards to the squashfs limitation, your could put multiple squashfs images on the same data DVD and mount them with loopback mode. You can even use the loopback drivers to merge them into a single partition. However, that would be a fairly complicated initialization. It might be better just to use the extra disk space to include binary packages for quicker emerge's.