Arabic would be nice, given the number of players who speak it, but for obvious reasons it's very unlikely to happen anytime in the near future (going right to left, symbols that change appearance depending on preceding and following symbols, &c.). There are currently no known active Chinese JJ2 players, or any other players from the Asian countries that use their own alphabets, so while technically we probably wouldn't mind implementing the appropriate character sets, it's not a priority, and I doubt anybody would feel dedicated enough to draw them. Cyrillic makes none of those problems and will probably be the first distinct alphabet to be implemented, although it's hard to even estimate when that would be. Out of the other letters you mention, Đ was always available in JJ2, and the other three should make it in even before the Cyrillic. A problem we'll run into in all of the aforementioned cases is the Windows-1252 encoding used by JJ2, which UTF-8 is not compatible with, and which is basically not expansible. There will be multiple incompatibilities with the existing parts of code that do anything related to text, from obtaining input to displaying it on the screen, because everything in JJ2 assumes single-byte characters. Therefore, yes, we have extending the character set in plans, but it will involve much more work than just drawing the glyphs and most people appear to be doing fine without them, so it doesn't look urgent.