> > It seems like you're trying to single out combining pairs as "less legitimate" when they're extensively used in the standard.
> I'm saying that Unicode only does it in English where it makes semantic sense to a native English speaker.
Well, combining characters almost never come up in English. The best I can think of would be the use of cedillas, diaereses, and acute accents in words like façade, coördinate and renownèd (I've been reading Tolkien's translation of Beowulf, and he used renownèd a lot).
Thinking about the Spanish I learned in high school, ch, ll, ñ, and rr are all considered separate letters (i.e., the Spanish alphabet has 30 letters; ch is between c and d, ll is between l and m, ñ is between n and o, and rr is between r and s; interestingly, accented vowels aren't separate letters). Unicode does not provide code points for ch, ll, or rr; and ñ has a code point more from historical accident than anything (the decision to start with Latin1). Then again, I don't think Spanish keyboards have separate keys for ch, ll, or rr.
Portuguese, on the other hand, doesn't officially include k or y in the alphabet. But it uses far more accents than Spanish. So, a, ã and á are all the same letter. In a perfect world, how would Unicode handle this? Either they accept the Spanish view of the world, or the Portuguese view. Or, perhaps, they make a big deal about not worrying about languages and instead worrying about alphabets ( http://www.unicode.org/faq/basic_q.html#4 ).
They haven't been perfect. And they've certainly changed their approach over time. And I suspect they're including emoji to appear more welcoming to Japanese teenagers than they were in the past. But (1) combining characters aren't second-class citizens, and (2) the standard is still open to revisions ( http://www.unicode.org/alloc/Pipeline.html ).