I still don't understand what's wrong with Han unification now that we have variation selectors, as well as... those characters that describe ways of laying out CJK character components relative to each other (I know I've seen these, but I have absolutely no idea what they're called and can't for the life of me figure out how to search for them).

(I think they should have unified Latin/Greek/Cyrillic, too, with variation selectors to disambiguate the overlaps. Yes, including special cases like the Greek question mark and Cyrillic multiocular O.)