I can give all kind of suggestions but there's no golden rule how to attract new members. Active ones are even harder. Apparantly, an upvote or leaving a comment is too.
If you ask me most people are not consequent, are not making a habit out of writing, joining and committing. They hope to be noticed but are not willing to invest.
Time is limited, energy, internet and the mood is too.

The value/prices go up a bit. I don't think people care about the interest. They go for the big whale or the steemitcurator...