I mostly agree, but some small communities, many years ago, would go by oldest, continuing from where you left off last time. That was fantastic for the sort of place where you wanted to read everything for whatever reason. If that could be put in on a community basis, it would be great :)

You can manipulate that by spamming new posts.

would be ideal if i can have many 'subscription groups', but in current form i simply can't subscribe to a community that's flooded with posts like news/politics.