You can't use savemiifrii on a full brick. The only option is Bootmii boot2 or to reflash your nand. If you could only install Bootmii as IOS then reflashing your nand is your only option and you will need a working nand backup or your keys to recover.
Autoboot recovery disks won't work at this point. I'm assuming you deleted your system menu IOS or tried installing your system menu to a stub? I see you said you bricked via an update but it wasn't an official update correct?