Right now we only have the Frontpage (subscribered communities), local (Instanz) and all, something I miss would a similar feature like multireddits we had on reddit. An own Feed or multiple different Feeds with each their own subscribed communities. Pluspoint if these communities do not show up in the Frontpage list :)
I would like this feature too. I could put all the c/news OR worldnews, c/technology, c/piracy and c/memes together. With the different c/piracy on different instances the feature can group them together like a one mega community that I can dive in with one press.