Reddit has original content too, we need Substeemits to work the same as they do in Reddit, with the option to have either a text post or a link post. Not all people can create original content, some are good at finding great content too, so why limit the options of what steemit can be, it can be both, a content aggregator and content creator.

Each SubSteemit should focus on a subject that it's members are interested in, I'm not sure about how should the moderators part be implemented here, maybe people can vote on moderators decision to avoid censorship or even SubSteemits without moderators, I'm not sure what is best, other people may have better suggestions about the implementation details.