I've said that the interface needs a like button as well, for new users especially. We often want to like something, but not necessarily increase the earnings for it.

I'm not certain about it diminishing the rewards though. Perhaps to a lesser degree than you suggested.

There are a lot of different ways that sites could go. I look forward to the future. It might be that we have dozens of smaller Steem based communities that each have their own sites. Some of them may be running on forks, while others are on the Steem blockchain, and even some of those may be on the blockchain, but separated.

I upvote comments to encourage them. Possibly occasionally more than I should. I have a different scale for good comments than good posts though. I think contributing to a post through comments is very important. I'm not certain the rewards should be reduced, even though some people abuse the system. I instead prefer reducing rewards for people that vote for the same people.