Side-by-side upvote/downvote buttons have a simplistic elegance. It also starts to shift the idea away from 'flagging' (does somebody review it? is it going to be censored) toward an action that establishes reward consensus for the post... which is what upvotes/downvotes actually are.
Even experienced Steemians sometimes forget that upvotes/downvotes are just a protocol mechanism to establish consensus on the distribution of the reward pool. They're not a tool for censorship, oppression, etc. Being downvoted doesn't mean anything except that somebody thinks your rewards were too high.
I gave you an upvote. If somebody thinks you're getting too much, they're probably wrong, but they can downvote to express their disagreement.