there's already existing "regional localizations" in the game (eg. changing the language option from english to german or russian via steam if u get what im trying to say). all relic needs to do is do a little programming and boom! u got native language option in the game.
There is ger as well as ru version of the game, there is obviously US/UK version. All with their own voice acting, so that is already done.
Still would likely require building new client, which is a considerable effort, more then ctrl+c ctrl+v.
Ah my i completly forgot. You are right. (both)
About programming their code is already rigid enough to prevent us from rejoining a game you just disconnected from so i doubt that will be a feature.
Kozo.