One thing I've thought about is giving certain privileges to different levels of steem power. On Tinder there is a feature where you can essentially mega upvote a user you like.
Maybe for every x amount of steempower you hold you could receive some sort of special vote you could use that doubles the upvote you normally have. Encouraging people to reach certain levels of steem power.
Also maybe you could receive a one time award for every x amount of steem you power up. (Others could suggest what this may be). Maybe a page similar to promoted feed that will bump users who power up into a higher "trending" spot on that feed.