Something that takes place about 50 years after Voyager would be good. Allows the writers the most freedom.
In fact, there have been novels regarding what's happened afterwards including the complete defeat of all Borg. Maybe the new show's producers could agree to make those novels canon in exchange for some funds from publishers since the new show would increase their book sales.
Star Trek Online follows this path. It's set I think 10 or 20 years after Voyager. About the only real think I liked in terms of story line along the quests is that they explain why Klingons today look different than the Klingsof of TOS time. That was a brief but interesting story.