isn't the real problem that you can't guarantee correct rendering of ideograph text without specifying fonts? there are japanese kanji that are drawn differently from the chinese hanzi they're descended from, but they're the same from a unicode perspective.

imagine if roman, greek, cyrillic, hebrew (aramaic), and ethiopian (ge'ez) were all assigned to the same group of code points and distinguishable only by font--they're all just variants of phoenician, after all....