I'd like to see the comment payout tweaked a bit. A flat 25% of the post reward could be way too much for many posts. Some posts are extremely valuable and do not require or warrant any discussion.
If that is the case, then the comments won't get up voted, take this post for instance, this post is extremely valuable, yet there are valid comments which have made me think and react, so I up-voted them. I think it can work well like this.
CG