What I think Steemit needs to look into is a karmic vouching/referral system for new accounts. If I vouch for someone, a new account can be registered using my uniquely created ref code, just for one new account.

This is a good idea. It will also help people spread the word that they are on steemit.

The problem arises when someone starts vouching for money, which often happens. "Vouches for sale" etc. So the concept is right, the execution would have to involve vouchers being reviewed and their vouch ability removed if it is found to be abused.