I think it should have additional options:

• Rewards based only in author upvote
• Limit the number of comments that can receive the reward
• Allow to manually assign an amount of the reward to the authors. This currently can only be done by authors that have the voting slider, requiring at least 500 Steem Power
• Spammers black list
• Forbid self-vote
• Do not count upvotes by @dustsweeper