It sounds like a good idea, however I wound't like Steemit to get the reputation of being an inclusive platform ruled by whales or anyone else for that fact. It should be open to all who want to share their ideas.
Spam and plagiarism need to be dealt with, no doubt about it. As for the single liners would be nice to see a system that rewards those of us that take the time to write more than a single line of text. A tiered system based on word count maybe would help encourage people to write more and share more.