one thing I like in Vimium C over Vimium is reload frame. Vimium it would reload the window and I have an older web app that uses frames where reloading the window resets everything back to a particular state and I have to go and reopen the frames.
The only problem I have is when I use the search (which, I know, is not HN itself but a separate service), it won't pick up the dropdown options as clickable.
It's not that high on HN? The left most column is upvote. Then the next button immediately to the right is the link. Next row buttons from left to right are username, comments (via hours link), hide, and comments again (normal link).