An issue I've thought of since then: the Armory soft-keyboard. It's not been any trouble to me, as I use the Western phonetic character set anyway, but it might improve Armory's worldwide appeal if the soft keyboard could handle alternatives. An argument could be made to permit use of multiple character sets for a single passphrase, as it would increase the size of the number domain, and hence add a little future proofing to passphrase security.
I can see that this would be a significant amount of perhaps unexciting work, but how does that trade off against worldwide appeal and passphrase security improvement?