I think I like the idea of 3 separated pool rewards. At least 2 separated pool for posts and comments the way @arhag propose really seems to make a lot of sense. I'll be awaiting more tinkering, details and comments to make a better opinion of those proposals. 

Also I'm not sure I understand the statement below. If comments don't have curation rewards then what will be the incentives to vote for those comments? 

> Comments should not have curation rewards because those who are reading have already found the discussion by other means.

What @smooth said is a no brainer in my opinion.

> Voting up the most insightful, entertaining, etc. comments can be both non-trivial effort and add a lot of value.