The hyphenation fix is not difficult but is language specific. I'm betting that German was somehow missed when they fixed the English and French. Kobo staff is reading the board a lot right now so maybe one of them will weigh in.
I have no idea if they have people fluent in the various supported languages involved in development or not. I do know that having people who use their Kobos in French has resulted in a better experience for Francophones. Maybe you could volunteer for the beta group.
There are things about formatting that bother me for sure. Some of them can be blamed on decisions or lack of action by the Kobo content developers (different than the device team, BTW). Others have to do with the CSS and HTML files the publishers submit. And then there are things related to Adobe and how Adobe handles such things.