Boot by committee (UEFI) doesn't seem much better than boot by fiat (BIOS). For everything nice it gives you, you lose something nice that BIOS gave you ... or you have something nice that you lose when you exit boot services. Or there's an extension for something nice that isn't usable on mainstream hardware.

UEFI gives you nicer video modes, but not a text mode after boot services.

UEFI has an extension for booting images from the network, but afaik, it's impossible to use, and there's no reasonable way to boot from a disk image; working UEFI network boot has to pull pieces out of the filesytem and present them seperately; as opposed to MEMDISK which makes the image available as a BIOS disk and the image is labeled so that one the OS is loaded, the image can be used without BIOS hooks. If this is possible on UEFI generally, it isn't widely distributed knowledge. Something that will work on any UEFI system that makes it to iPXE, subject to changes to the OS in the image (which is reasonable... MEMDISK needs changes too, unless the OS runs all disk I/O through BIOS APIs)