Yes we should have downvotes but I think we should be able to see who downotes us (equivalent to "likes" on Facebook). I think that would deter trolls and users with multiple accounts from simply downvoting for no reason or only because they dislike the answerer because their name would be seen.
No I would think better not because some members are upset by the downvotes . Also it helps to prevent trolls in a way
That might be important feature to some people, but I don't really find it that helpful
Keep them, but show who gave the downvote to identify the trolls
Yes and no. Whenever I downvote something that could use work I do give constructive criticism, but a lot of the time people just say things that are downright stupid. It's like did you think about that before you wrote it? In which case the downvote doesn't even need explaination