> Well, I'd love to be able to drop a bunch of 8GB (notably FAT doesn't support files this big) LiveDVD disk images on a bare file system and see them in the computer's built-in boot-menu immediately. I already enjoy the fact I don't need a traditional boot loader (like GRUB) to handle multi-OS as I can have 2 independent EFI boot partitions (one for Windows and one for Linux) and use the computer's boot menu too choose which to boot from.

Different systems have different constraints. For example, loading the firmware interface on my systems so it can present a boot menu is way, way slower than rEFInd or Grub. And presents an ugly menu in a non-native resolution for my monitors. And doesn't let me override kernel parameters adhocly at boot time if needed (thought it has been a number of years since I have, I'm reluctant to let go of the option).