That's an interesting idea. As an immediate response, I think if I made my votes visible, then my upvotes would outnumber my downvotes even more than (I believe) they do now. If that reaction is general, and if participants buy in to making their votes visible in the first place, that could substantially increase the ratio of upvotes to downvotes. In turn, most users would be happier, as most seem to be more dismayed by themselves getting downvotes than by somebody else getting upvotes.
Your reason number 1 for doing this is also why I would hope that some regular participants here would disclose their votes.