Yeah commentrewarder is great for that, especially if the author distributes the extra rewards well. It would in many ways encourage people to spend their limited 10x max daily votes well if they thought that actually consuming the content and having something nice to comment about it would get them an extra % of the vote you just placed back. 

At the same time the author could potentially receive more rewards even if they placed 10% to go to the comments because curators who don't care about commenting see the amount of engagement it's generating and want to reward that author more that day instead of what they usually would've voted. It's kind of a win-win-win situation if it ends up giving less rewards to other authors who may not get a lot of engagement or may not care about it.