It could probably be argued that needing this plugin is actually a symptom that you need to rethink some part of your UI. If an element is important enough to be pointed out like this, it should perhaps feature more prominently in the layout.
With hidden upvotes the only way to show assent is to comment. Actually as a hack for no comment scores I think I could come to appreciate a string of "agreed" comments as a visual indicator.
It's redundant elsewhere, it's not here.