I don't upvote comments anymore. I used to reward pretty much all the comments on my posts but that was in the day when my less than 500sp was worth 16cents upvote! I found out the minimum payout for posts was around 2 to 3 cents a long time before the last HF. I think the main difference since the last HF is in the curation curve thing. You get a better return on your investment (upvote) if the post is popular (receives more upvotes) and comments are not likely to get large numbers of upvotes. It is hard to say if it is the fault of the HF that there are less upvotes or the general price of steem. I used to be able to give a 3 cents with less than 20% upvote (and I had a much lower SP than now). Now I can't even get 2cents with a 100% upvote. I think there is less engagement with comments than before. And yes I miss the surprise upvotes, sometimes worth more than my posts for a whole week!