Presently, change of the UI language (menus, user documentation, training, missions, campaigns, cockpits, etc.) is done manually by repairing DCS installation. During the repair some of other language files (e.g. flight manuals, training missions and videos) are deleted and replaced with their versions in the selected language. I personally, prefer having docs and missions of Russian aircrafts in Russian, while keeping other mods in English.
Could we just have an option on the main DCS screen allowing quick switch from one language to another without re-torrenting and deleting other languages' files?