And since everybody reinstates their wishlist, I’ll contribute my two bits, actually just one: BiDi support.
Judging by my Hebrew support experience, it seems that bi-directional text is already supported to some extent. (That’s why I picked EmEditor in the first place. I tried at least half a dozen other editors before I decided on it.) UNICODE is supported, and Windows has built-in Bi-Di support too. Doesn’t the support of Japanese also require Bi-Di support?
So, aren’t you already half way there? Would it be such a major undertaking? I hope you have at least plans to support it one day, do you?