UEFI is a fairly insane spec, but at least it's a fairly complete spec. Following it is preferable to custom nonsense. (Spoken as someone writing a custom non-UEFI bootloader right now)
Whenever I think of how various parts are insane, I'm reminded of numerous cases in different systems in the past where I missed the insane part I am reading about...
Like the entire HII thing, with an UI toolkit!