I'm from Czech Republic, so I don't feel good to explain myself in other languages, so sorry for confusion and also that is one of reasons I need following add-ons. Also for that reason, I probably missed some already released add-ons which I could use in my short trying-to-get-familiar-spell, so please feel free to advise.
I'd like to have a truly multilingual discussion and I need following add-ons (which might be useful even for a general public):
1. post summary add-on - each post to have one more optional text field which would allow write a resume/summary of a post so anybody don't have to bother reading the whole post if not interested
2. post/discussion quality and obsoleteness ranking add-on with discussion list ordered by that rank (maybe two add-ons?) - ability to vote about post and also a discussion quality - ability to rank discussions as obsolete - discussion list ordered by some index counted from quality and obsoleteness (as an option to user of course)
3. translation add-on - ability to have more versions of a post in other languages - display posts in language versions by user language settings (might co-work with some existing add-ons to get language priorities) and post language version availability - new Role 'Translator' which will have create/edit ability and permission to all non-original versions of posts. - should work with "1. post summary add-on" so translators team would translate only summaries if quality of the post is not high.
I'm going to write all this so if you know about anything helpful I would appreciate it.
I'm going to start with "1. summary add-on" since it looks as the easiest one.
Also I was thinking about automated translations by some third-party software or some web service, which might be used before you got setup a translation team or also working together as well.