That is a great idea. But I don't think Steemit will ever follow a reddit like model. It will most likely follow a Quora like model without any specific community. If it intended to be like Reddit or stack exchange, (where there is separate communities) it would have started adding features like that. It's over a year since steem launched.

Steemit doesn't allow non sourced and copy pasted content even if that contents original owner permits it. I think it is not practical to compare it to reddit where people post whatever they wish. It is not like Steemit doesn't want to allow it, they can't allow it.

If they allowed copy pasted content, the copyright police would put them in great legal trouble. They aren't coming because steemit isn't popular now. Only 30000 people use it every day. Copyrighters go after only the big ones. You will see Hollywood go after YouTube but not Vimeo (which is a spec compared to YouTube).