lmce3000 - as you correctly noted, MD and wireless are going to be the issue if you want it portable.... my thoughts are
1 - it is possible that disked MD will be added back in eventually, that would mean it could use wireless, only thing is getting a "disk" large enough as SSD's of that size will be very expensive!
2 - it is possible that you could set up a flash/thumb GRUB/PXE boot process, boot from flash, start GRUB, load a wireless driver pre-configured for your SSID/encryption, then kick off the PXE boot from GRUB.