Additionally i hope...;
. "Inline input" with Japanese IME. < currently not inline. is it only on Windows ?
. Full support of Japanese characters (it can't display some symbol chars now).
// maybe multi(separates alphabet and Japanese chars) font setting can solve it.
. Word shift(?) with Ctrl+RightArrow key in Japanese. (it jumps line end now
. Support of some Japanese character encoding (SJIS, EUC-JP).
. Japanese menu text. (Should I directly edit .sublime-menu files ?)